OCR A-Level Chemistry with well
explained study guide
1. Acid - correct answer.💖💖💖💖✔<<<<<A species
that releases H+ ions in aqueous solution
2. Acid Dissociation Constant Ka - correct
answer.💖💖💖💖✔<<<<<The equilibrium constant
that shows the extent of dissociation of a weak acid
3. Acid-Base Pair - correct answer.💖💖💖💖✔<<<<<A
pair of two species that transform into each other by gain
or loss of a proton
4. Activation Energy - correct
answer.💖💖💖💖✔<<<<<The minimum energy
required to start a reaction by the breaking of bonds
5. Actual Yield - correct answer.💖💖💖💖✔<<<<<The
amount of product obtained from a reaction
6. Addition Polymerisation - correct
answer.💖💖💖💖✔<<<<<Formation of a very long
molecular chain, by repeated addition reactions of many
unsaturated alkene molecules (monomers).
7. Addition Reaction - correct
answer.💖💖💖💖✔<<<<<A reaction in which a
reactant is added to an unsaturated molecule to make a
one saturated molecule
,8. Adsorption - correct answer.💖💖💖💖✔<<<<<The
process that occurs when a gas or liquid or solute is held to
the surface of a solid.
9. Alicyclic - correct
answer.💖💖💖💖✔<<<<<Containing carbon atoms
joined together in a ring that is not aromatic
10. Aliphatic - correct
answer.💖💖💖💖✔<<<<<Containing carbon atoms
joined together in straight or branched chains.
11. Alkali - correct answer.💖💖💖💖✔<<<<<A type
of base that dissolves in water forming hydroxide ions, OH-
(aq) ions.
12. Alkanes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with single carbon-to-
carbon bonds
13. and the general formula: CnH2n+2.
14. Alkenes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with at one double
carbon-to-carbon
15. bonds and the general formula: CnH2n.
16. Alkyl Group - correct answer.💖💖💖💖✔<<<<<A
side chain formed by removing a hydrogen atom removed
from an
17. alkane parent chain, for example, CH3, C2H5; any
alkyl group is often shown
18. as R.
,19. Alkynes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with one triple carbon-to-
carbon bonds and the general formula: CnH2n-2.
20. Amount of Substance - correct
answer.💖💖💖💖✔<<<<<The quantity whose unit of
the mole, used as a means of counting any species such as
atoms, ions and molecules.
21. Anhydrous - correct
answer.💖💖💖💖✔<<<<<Containing no water
molecules
22. Anion - correct answer.💖💖💖💖✔<<<<<A
negatively charged ion with more electrons than protons
23. Aromatic - correct
answer.💖💖💖💖✔<<<<<Containing one or more
benzene rings
24. Atom Economy - correct
answer.💖💖💖💖✔<<<<<((sum of molar masses of
desired products)/(sum of molar masses of all products)) x
100%.
25. Atomic (Proton) Number - correct
answer.💖💖💖💖✔<<<<<The number of protons in
the nucleus of an atom
26. Atomic Orbital - correct
answer.💖💖💖💖✔<<<<<A region around the
nucleus that can hold up to two electrons with opposite
spins
, 27. Average Bond Enthalpy - correct
answer.💖💖💖💖✔<<<<<The average enthalpy
change that takes place when breaking by homolytic
fission 1 mol of a given type of bond in the molecules of a
gaseous species.
28. Avogadro's Constant - correct
answer.💖💖💖💖✔<<<<<The number of atoms per
mole of the carbon-12 isotope. (6.02 × 10^23 mol-1 ).
29. Base - correct answer.💖💖💖💖✔<<<<<A
compound that neutralises an acid to form a salt
30. Binary Compound - correct
answer.💖💖💖💖✔<<<<<A compound containing 2
elements only
31. Bond Angle - correct
answer.💖💖💖💖✔<<<<<The angle between 2 bonds
at an atom
32. Bond Dissociation Enthalpy - correct
answer.💖💖💖💖✔<<<<<The enthalpy change that
takes place when breaking by homolytic fission 1 mol of a
given bond in the molecules of a gaseous species.
33. Bonded Pair - correct
answer.💖💖💖💖✔<<<<<A pair of electrons shared
between 2 atoms to make a covalent bond
34. Brønsted-Lowry acid - correct
answer.💖💖💖💖✔<<<<<A species that is a proton,
H+, donor
explained study guide
1. Acid - correct answer.💖💖💖💖✔<<<<<A species
that releases H+ ions in aqueous solution
2. Acid Dissociation Constant Ka - correct
answer.💖💖💖💖✔<<<<<The equilibrium constant
that shows the extent of dissociation of a weak acid
3. Acid-Base Pair - correct answer.💖💖💖💖✔<<<<<A
pair of two species that transform into each other by gain
or loss of a proton
4. Activation Energy - correct
answer.💖💖💖💖✔<<<<<The minimum energy
required to start a reaction by the breaking of bonds
5. Actual Yield - correct answer.💖💖💖💖✔<<<<<The
amount of product obtained from a reaction
6. Addition Polymerisation - correct
answer.💖💖💖💖✔<<<<<Formation of a very long
molecular chain, by repeated addition reactions of many
unsaturated alkene molecules (monomers).
7. Addition Reaction - correct
answer.💖💖💖💖✔<<<<<A reaction in which a
reactant is added to an unsaturated molecule to make a
one saturated molecule
,8. Adsorption - correct answer.💖💖💖💖✔<<<<<The
process that occurs when a gas or liquid or solute is held to
the surface of a solid.
9. Alicyclic - correct
answer.💖💖💖💖✔<<<<<Containing carbon atoms
joined together in a ring that is not aromatic
10. Aliphatic - correct
answer.💖💖💖💖✔<<<<<Containing carbon atoms
joined together in straight or branched chains.
11. Alkali - correct answer.💖💖💖💖✔<<<<<A type
of base that dissolves in water forming hydroxide ions, OH-
(aq) ions.
12. Alkanes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with single carbon-to-
carbon bonds
13. and the general formula: CnH2n+2.
14. Alkenes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with at one double
carbon-to-carbon
15. bonds and the general formula: CnH2n.
16. Alkyl Group - correct answer.💖💖💖💖✔<<<<<A
side chain formed by removing a hydrogen atom removed
from an
17. alkane parent chain, for example, CH3, C2H5; any
alkyl group is often shown
18. as R.
,19. Alkynes - correct answer.💖💖💖💖✔<<<<<The
hydrocarbon homologous series with one triple carbon-to-
carbon bonds and the general formula: CnH2n-2.
20. Amount of Substance - correct
answer.💖💖💖💖✔<<<<<The quantity whose unit of
the mole, used as a means of counting any species such as
atoms, ions and molecules.
21. Anhydrous - correct
answer.💖💖💖💖✔<<<<<Containing no water
molecules
22. Anion - correct answer.💖💖💖💖✔<<<<<A
negatively charged ion with more electrons than protons
23. Aromatic - correct
answer.💖💖💖💖✔<<<<<Containing one or more
benzene rings
24. Atom Economy - correct
answer.💖💖💖💖✔<<<<<((sum of molar masses of
desired products)/(sum of molar masses of all products)) x
100%.
25. Atomic (Proton) Number - correct
answer.💖💖💖💖✔<<<<<The number of protons in
the nucleus of an atom
26. Atomic Orbital - correct
answer.💖💖💖💖✔<<<<<A region around the
nucleus that can hold up to two electrons with opposite
spins
, 27. Average Bond Enthalpy - correct
answer.💖💖💖💖✔<<<<<The average enthalpy
change that takes place when breaking by homolytic
fission 1 mol of a given type of bond in the molecules of a
gaseous species.
28. Avogadro's Constant - correct
answer.💖💖💖💖✔<<<<<The number of atoms per
mole of the carbon-12 isotope. (6.02 × 10^23 mol-1 ).
29. Base - correct answer.💖💖💖💖✔<<<<<A
compound that neutralises an acid to form a salt
30. Binary Compound - correct
answer.💖💖💖💖✔<<<<<A compound containing 2
elements only
31. Bond Angle - correct
answer.💖💖💖💖✔<<<<<The angle between 2 bonds
at an atom
32. Bond Dissociation Enthalpy - correct
answer.💖💖💖💖✔<<<<<The enthalpy change that
takes place when breaking by homolytic fission 1 mol of a
given bond in the molecules of a gaseous species.
33. Bonded Pair - correct
answer.💖💖💖💖✔<<<<<A pair of electrons shared
between 2 atoms to make a covalent bond
34. Brønsted-Lowry acid - correct
answer.💖💖💖💖✔<<<<<A species that is a proton,
H+, donor
