Insert answer code

Test building version of the database. Find questions then select the Build checkbox and click 'Collect' - the hyperlink at the bottom will build up as you navigate to more questions and do more collecting. To remove any questions from the test, uncheck the checkbox.

Finding the most difficult questions in the database based on the percentage of students who got it correct. A low percentage indicates the question is quite difficult. The questions are presented in order starting with the toughest. Some of them have come from the examiner comment. Note this only works for some questions since not all questions have ever been answered or mentioned in examiner comments. Some topic/keyword combinations will therefore yield zero results.

Finding the least difficult questions in the database based on the percentage of students who got it correct. A high percentage indicates the question is quite easy. The questions are presented in order starting with the easiest. Some of these have come from the examiner comment. Note this only works for some questions since not all questions have ever been answered or mentioned in examiner comments. Some topic/keyword combinations will therefore yield zero results.

Choose board, year or topic from the menus above to see more questions

A

B

C

D

show solution

Build  

A

B

C

D

show solution

Build  

A

B

C

D

show solution

Build  

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.

A

B

C

D

show solution

Build  

Maybe you could help other users of this database by tagging a topic and a keyword.    Click here if you do not wish to help

Keyword:	KEYWORD - acid and alkali acid and base acid and carbonate acid and metal acid concentration acid rain acidic organic molecules acidic oxide acidity acids activation energy air air pollution alcohol alcohols alkanes alkanes -combustion alkanes -substitution alkanes and alkenes alkanes, alkenes and alcohols alkenes alkynes allotropes of carbon alloys aluminium ammonia ammonia and sulphur ammonium chloride & calcium hydroxide ammonium sulphate production amount of substance amphoteric oxide analgesic- apparatus arrangement of particles atom ion & molecule atomic structure balancing barium and silver salts basic oxides better conductor blast furnace boiling point bond energy bonding bromination brownian motion burette burning coal burning sulphur calcium calcium carbonate carbon carbon cycle carbon dioxide carbon dioxide & methane carbon monoxide carbonates catalyst catalytic converter cellulose CFC change of state chemical change choice of equipment choice of method cholesterol chromatography coal collecting gas colloid- combining powers combustion complete combustion compounds concentration conduction in metals contact process cooling cooling curves copper copper plating copper sulphate covalent bonding cracking cracking hydration combustion crude oil crystallisation decomposition diamond diatomic molecules diffusion displacement displacement reactions distillation dot cross diagram double bonds drinking water drugs from plants duplicate dyes- dynamic equilibrium economics effect of temp - rates of reaction electrical conductor electrictrical conductor electrochemical cell electrolysis electrolysis of aqueous sodium chloride electrolysis of conc HCl electrolysis of conc NaCl electrolysis of copper chloride electrolysis of copper sulphate soln electrolysis of dilute sulphuric acid electrolysis of lead bromide electrolysis of molten NaCl electronic arrangement electronic structure electroplating elements elements compounds and mixtures elements in ... empirical and molecular formula empirical formula emulsion- endothermic endothermic exothermic energetics energy change for reaction energy changes energy given out energy level diagram energy profile energy sources enthalpy change equations equilibrium equilibrium position equilibrium yield equipment error ester ethanoic acid ethanoic acid + metal ethanol ethanol + potassium dichromate ethanol as fuel ethene eutrophication exothermic exothermic stages in water formation extracting aluminium extracting copper extracting metals extracting metals -zinc extracting salt extraction of aluminium extraction of metals extraction of metals -iron extraction of zinc fastness of dye- fats carbohydrates & proteins fermentation flame tests formula fossil fuel fractional distillation fractional distillation of air fruit cell fuel cells fuels functional groups galvanised gas tests gel and suspension- giant molecular structure glass graphite greenhouse effect greenhouse gases group 0 group 1 group 1 and 7 group 1 and transition elements group 2 group 3 group 4 group 6 group 7 groups haber process half equations hardness in water HCl HCl + barium nitrate heating carbonate helium homolgous series household acids hydration hydration of alkene hydration of salt hydrides hydrocarbon hydrogen as a fuel hydrogen gas hydrogenation hydrolysis hydroxide identify acid identify compound identify compound from structure identify element identify gas identify ions identify liquid identify metal identify reactants identify salt identify solution impurity melting point boiling point indicators insoluble nitrate intermolecular forces ion formation ionic and covalent ionic bonding ionic compounds ionic equation ionic half equations ionisation ions ions in water ions present iron isomers isotopes kinetic theory lead nitrate + sulphuric acid lime limestone limestone and salt linkages litmus macro molecules mass of gases at rtp mass produced mass remaining maximum mass obtained melting point metal and non metal oxides metal ores metal oxide metallic bonding metals metals and non metals methane mixture molecular formula molecules moles naming natural gas neutralisation nitrates nitrates -decomposition nitrates and carbonates non-acidic gases non-metals NPK fertiliser nucleon number number of atoms number of atoms in molecule number of electrons number of ions number of molecules number of moles number of moles -combustion of alkane number of moles in reaction number of protons numbers of protons electrons and neutrons nylon obtaining carbon monoxide obtaining magnesium obtaining oxygen organic acid organic compounds organic formula oxidation oxidation and reduction oxidation and reduction at electrode oxidation of alcohol oxidation of ethanol oxidation state oxides oxides of carbon oxides of metals oxides of nitrogen oxides of non metals oxygen partially permeable membrane particle theory percentage by mass percentage yield periodic table periodic trends petroleum pH photosynthesis physical and chemical change pollution polymer polymer hydrolysed polymerisation polymers position in periodic table position of equilibrium precipitation production of gas properties properties of acids properties of elements properties of gases properties of materials properties of metals properties of oxides protein hydrolysis proteins proton number purity radioactive isotopes rates of reaction ratio of number of molecules raw materials reacting gases reacting masses reacting moles reacting with HCl reaction products reaction scheme reaction with bromine reactions of metals reactivity reactivity series reactivity trends in periodic table recycling glass redox reduction reduction of oxide refining oil relative atomic mass relative formula mass relative molecular mass renewable energy source reversible reactions rusting salts salts -preparation sand scattering a beam of light selecting apparatus separating gases separation separation techniques simple and giant molecular structure simple cell sodium sodium chloride sodium hydroxide soil acidity solids liquids and gases solubility solubility of salts solute effect on melting and boiling point solution solvents stainless steel state symbols steel strong acid strong and weak acid structural formula structure structure - carbon structure of glass structures substances obtained from rocks substitution reaction needing light sulphates sulphur sulphur dioxide sulphuric acid synthetic dyes test for ammonia test for carbon dioxide test for chlorine test for gases test for ions test for presence of water test for water test for water purity tests for common chemicals the mole thermal decomposition thermometer titration transition elements trends universal indicator unsaturated uranium uses for water uses of calcium carbonate uses of metals volcanic gas volume of gas water water purification weak acid weathering of rocks welding torch word equations writing equations	this is topic box
Topic:	TOPIC-acids bases and saltsair and wateratomic structure & bondingcarbonateschemical change -energetics -rates of reaction -eqchemical change -energetics -rates of reaction -equilibriumchemical industrychemical reactions -laboratory tests for ions andchemical reactions -laboratory tests for ions and gasescolloidsduplicatedyes and drugselectricity and chemistryenvironmentexperimental techniquesmetalsorganic chemistryoxidation and reductionparticlesphysical changestoichiometry and molessulphurthe periodic tabletopic	topic box
HINT: Tag keyword first and a found topic may be added automatically.