1. Substance that produces hydrogen ions H+ in aqueous solution.
Acid
Substance that produces
hydrogen ions H+ in aqueous solution.

2. Acid Rain
Form of pollution when acidic air pollutants such as sulphur dioxide and nitrogen dioxide react with water in the atmosphere.

3. Activation Energy
Minimal amount of energy that reactant particles must possess in order for a chemical reaction to occur.

4. Addition Polymerisation
Process that occurs when unsaturated monomers join together without losing any molecules or atoms. The polymer formed is called an addition polymer.

5. Air Pollution
Condition in which air contains a high concentration of chemicals that may harm living things or damage non-living things.

6. Alcohols
Homogenous series of organic acids which have the hydroxyl (-OH) functional group.

7. Substance that produces hydroxide ions OH- in aqueous solution.
Alkali
Substance that produces
hydroxide ions OH- in aqueous solution.

8. Homologous series of hydrocarbons that contain only
Alkanes
Homologous series of hydrocarbons that contain only
carbon-carbon single covalent bonds.

9. Homologous series of hydrocarbons that contain
Alkenes
Homologous series of hydrocarbons that contain
one or more carbon-carbon double bonds.

10. one or a few other elements.
Alloy
Mixture of a metal with
one or a few other elements.

11. Negative ions that are formed when atoms gain electrons.
Anions
Negative ions that are formed when atoms gain electrons.

12. Atom
The smallest particle of an element that retains the properties of that element.

13. Base
Any metal oxide or hydroxide that reacts with an acid to produce a salt and water only.

14. Mechanism that maintains the level of carbon dioxide
Carbon Cycle
Mechanism that maintains
the level of carbon dioxide
in the atmosphere.

15. Carboxylic Acids
Homogenous series of organic acids which have the carboxylic (-COOH) functional group.

16. Catalyst
Substance which increases the speed of a chemical reaction and remains chemically unchanged at the end of the reaction.

17. Positive ions that are formed when
Cations
Positive ions that are formed when
atoms lose electrons.

18. Chemistry
The study of composition, structure and properties of matter, the changes in which matter undergoes and the energy accompanying these changes.

19. Breaking down long-chain hydrocarbons into smaller molecules.
Cracking
Breaking down long-chain hydrocarbons into smaller molecules.

20. Method for separating two or more components that
Chromatography
Method for separating two or more components that
dissolve in the same solvent.

21. Compounds containing elements carbon, fluorine and chlorine.
Chlorofluorocarbons
Compounds containing elements carbon, fluorine and chlorine.
Erodes the ozone layer when released to the atmosphere.
Commonly known as CFCs.

22. Compound
A compound is a pure substance containing two or more elements that are chemically combined into a fixed ratio.

23. Concentration of Solution
Amount of solute dissolved in unit volume of the solution.

24. Condensation polymerisation
Process occurs when monomers combine to form a polymer,
with the removal of a small molecule
such as water.

25. Process used for obtaining a pure solid sample from its solution.
Crystallisation
Process used for obtaining a pure solid sample from its solution.

26. from a region of higher concentration
Diffusion
Movement of particles
from a region of higher concentration
to a region of lower concentration.

27. Bond formed by the sharing of electrons between two atoms.
Covalent Bond
Bond formed by the sharing of electrons between two atoms.

28. (Simple) Distillation
Process used to separate a pure solvent from a solution.

29. (Fractional) Distillation
Process used to separate a mixture of miscible liquids with different boiling points.

30. Element
Pure substance that
cannot be broken down into two or more simpler substance by chemical processes.

31. Electrolysis
Process of using electricity to break down or decompose a compound (usually an ionic compound in the molten state or in aqueous solution).

32. Electroplating
Process of depositing a layer of metal on another substance using electrolysis.

33. A change in which heat is absorbed from the surroundings.
Endothermic Change
A change in which heat is absorbed from the surroundings.
Total energy absorbed for bond breaking > total energy releases for bond making.

34. ∆H represents the difference in energy of the reactants and products.
Enthalpy Change
∆H represents the difference in energy of the reactants and products.

35. Substances that catalyse the chemical reactions in plants and animals.
Enzymes
Substances that catalyse the chemical reactions in plants and animals.
They are biological catalysts.

36. A change in which heat is given out to the surroundings.
Exothermic Change
A change in which heat is given out to the surroundings.
Total energy absorbed for bond breaking < total energy releases for bond making.

37. Evaporation to Dryness until all the water has boiled off.
Process used to obtain a soluble solid from a solution by heating the solution
until all the water has boiled off.

38. Global Warming
Increase in the Earth’s average temperature due to the build-up of greenhouse gases in the atmosphere.

39. separate insoluble and solid particles
Filtration
Process used to
separate insoluble and solid particles
from a liquid.

40. Functional Group
Atom or group of atoms that gives a molecule its characteristic properties.

41. Homologous Series
Family of organic compounds with the same functional group and similar chemical properties.

42. Ionic Bonding
Ionic bonds are the strong electrostatic forces of attraction between positive and negative ions.

43. Ionic Equation
Shows the ions that take part in a reaction. It leaves out the spectator ions that do not react.

44. Isomers
Compounds that have the same molecular formula but different structural formulae.

45. Atoms of the same element with the
Isotopes
Atoms of the same element with the
same number of protons and electrons,
but different number of neutrons.

46. Kinetic Particle Theory
This theory states that
all matter is made up of tiny particles and
that these particles are
in constant random motion.

47. made up of many small molecules.
Macromolecule
Large molecule that is
made up of many small molecules.

48. Bond formed by the force of attraction between positive metal ions and
Metallic Bond
Bond formed by the force of attraction between positive metal ions and
the ‘sea of mobile electrons’.

49. Made up of two or more substances that are not chemically combined.
Mixture
Made up of two or more substances that are not chemically combined.

50. Amount of substance in 6 x 1023 particles.
Mole
Amount of substance in 6 x 1023 particles.

51. Molecule
A group of two or more atoms that are chemically combined (joined together).

52. Process where hydrogen ions H+ from acid and the hydroxide ions OH-
Neutralization
Process where hydrogen ions H+ from acid and the hydroxide ions OH-
react to form water.

53. Number of protons and neutrons in the atom.
Nucleon Number
Number of protons and neutrons in the atom.

54. Oxidation
Process in which a substance gains oxygen, loses hydrogen, loses electrons, or when its oxidation state increases.

55. Substance that causes another substance to be oxidised.
Oxidation Agent
Substance that causes another substance to be oxidised.

56. Oxidation State
The charge of an atom of an element would have if it existed as an ion in a compound.

57. Periodic Table
List of elements arranged in order of increasing proton (atomic) numbers.

58. mixture of hydrocarbons (mainly alkanes).
Petroleum
Naturally occurring
mixture of hydrocarbons (mainly alkanes).

59. Fats or oils contain more than one carbon-carbon double bond.
Polyunsaturated
Fats or oils contain more than
one carbon-carbon double bond.

60. Number of protons in the atom.
Proton Number
Number of protons in the atom.

61. Pure Substance
Made up of one single element or compound. Not mixed with any other substance. A pure solid has an exact and constant melting point, while a pure liquid has an exact and constant boiling point.

62. Rf value
Ratio of 𝑫𝒊𝒔𝒕𝒂𝒏𝒄𝒆 𝒕𝒓𝒂𝒗𝒆𝒍𝒍𝒆𝒅 𝒃𝒚 𝒔𝒖𝒃𝒔𝒕𝒂𝒏𝒄𝒆 𝑫𝒊𝒔𝒕𝒂𝒏𝒄𝒆 𝒕𝒓𝒂𝒗𝒆𝒍𝒍𝒆𝒅 𝒃𝒚 𝒕𝒉𝒆 𝒔𝒐𝒍𝒗𝒆𝒏𝒕

63. reduction of another substance.
Redox Reaction
A chemical reaction which involves the oxidation of a substance and the
reduction of another substance.

64. Substance that causes another substance to be reduced.
Reducing Agent
Substance that causes another substance to be reduced.

65. Reduction
Process in which a substance loses oxygen, gains hydrogen, gains electrons, or when its oxidation state decreases.

66. 𝑨𝒗𝒆𝒓𝒂𝒈𝒆 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒐𝒏𝒆 𝒂𝒕𝒐𝒎 𝒐𝒇 𝒆𝒍𝒆𝒎𝒆𝒏𝒕 𝟏 𝟏𝟐 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒂𝒏 𝒂𝒕𝒐𝒎 𝒐𝒇 𝒄𝒂𝒓𝒃𝒐𝒏−𝟏𝟐
Relative Atomic Mass
𝑨𝒗𝒆𝒓𝒂𝒈𝒆 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒐𝒏𝒆 𝒂𝒕𝒐𝒎 𝒐𝒇 𝒆𝒍𝒆𝒎𝒆𝒏𝒕 𝟏 𝟏𝟐 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒂𝒏 𝒂𝒕𝒐𝒎 𝒐𝒇 𝒄𝒂𝒓𝒃𝒐𝒏−𝟏𝟐

67. Relative Molecular Mass
𝑨𝒗𝒆𝒓𝒂𝒈𝒆 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒐𝒏𝒆 𝒎𝒐𝒍𝒆𝒄𝒖𝒍𝒆 𝒐𝒇 𝒆𝒍𝒆𝒎𝒆𝒏𝒕 𝒐𝒓 𝒄𝒐𝒎𝒑𝒐𝒖𝒏𝒅 𝟏 𝟏𝟐 𝒎𝒂𝒔𝒔 𝒐𝒇 𝒂𝒏 𝒂𝒕𝒐𝒎 𝒐𝒇 𝒄𝒂𝒓𝒃𝒐𝒏−𝟏𝟐

68. Chemical process that can go both forward and backward
Reversible Reaction
Chemical process that can
go both forward and backward
at the same time.

69. Device used to separate a mixture of immiscible liquids.
Separating Funnel
Device used to separate
a mixture of immiscible liquids.

70. Device that converts chemical energy into electrical energy.
Simple Cell
Device that converts chemical energy into electrical energy.
It is also known as an electric cell.

71. An alloy of iron with carbon and/or other metals.
Steel
An alloy of iron with carbon and/or other metals.

72. Acid that is completely ionised in aqueous solution.
Strong Acid
Acid that is completely ionised in aqueous solution.

73. Process used to separate solid that sublimes from one that does not.
Sublimation
Process used to separate solid that sublimes from one that does not.

74. Weak acid is an acid that is only
partially ionised in aqueous solution.