AQA A LEVEL CHEMISTRY
PAPER 1 QUESTIONS AND
VERIFIED CORRECT
ANSWERS GRADED A+
LATEST 100% GUARANTEED
PASS
Why does ionization energy increase across a period? - CORRECT ANSWER-Atoms get smaller,
nuclear charge increases, similar shielding
Dip in ionisation energy groups 2-3 - CORRECT ANSWER-Electrons take up higher orbital (s to p)
which makes ionisation energy lower as higher orbitals have higher energy
Dip in ionisation energy groups 5-6 - CORRECT ANSWER-Electron- electron repulsion in orbital
makes electron easier to lose
Relative atomic mass - CORRECT ANSWER-The average mass of an atom of an element/ 1/12th
of the mass of an atom of carbon-12
Empirical formula - CORRECT ANSWER-The simplest whole number ratio of atoms of each
element present in a compound
Percentage yield - CORRECT ANSWER-actual yield/theoretical yield x 100
, Atom economy - CORRECT ANSWER-(Molecular mass of desired products/ Molecular mass of all
products) x 100
Electronegativity - CORRECT ANSWER-The power of an atom to attract electron density in a
covalent bond towards itself
electronegativity trend - CORRECT ANSWER-increases across a period, decreases down a group
Enthalpy change - CORRECT ANSWER-Heat energy change measured at constant pressure
Hess's Law - CORRECT ANSWER-The Enthalpy Change for a chemical reaction is independent of
the route taken
Mean bond enthalpy - CORRECT ANSWER-Energy required to break one mole of covalent bonds
between two given atoms, averaged across a range of compounds
Activation energy - CORRECT ANSWER-the minimum energy colliding particles must have in
order to react
dynamic equilibrium - CORRECT ANSWER-Forward and backward reactions take place at same
rate so concentrations of products and reactants remain constant
Only reached in closed system
Le Chatelier's Principle - CORRECT ANSWER-When a system at equilibrium is disturbed, the
equilibrium shifts in the direction that reduces the disturbance
Haber process conditions - CORRECT ANSWER-- 200 atm : high pressures favour forwards
reaction but are costly
- 450°C : low temperature favours towards reaction but rate of reaction too slow at low temps
PAPER 1 QUESTIONS AND
VERIFIED CORRECT
ANSWERS GRADED A+
LATEST 100% GUARANTEED
PASS
Why does ionization energy increase across a period? - CORRECT ANSWER-Atoms get smaller,
nuclear charge increases, similar shielding
Dip in ionisation energy groups 2-3 - CORRECT ANSWER-Electrons take up higher orbital (s to p)
which makes ionisation energy lower as higher orbitals have higher energy
Dip in ionisation energy groups 5-6 - CORRECT ANSWER-Electron- electron repulsion in orbital
makes electron easier to lose
Relative atomic mass - CORRECT ANSWER-The average mass of an atom of an element/ 1/12th
of the mass of an atom of carbon-12
Empirical formula - CORRECT ANSWER-The simplest whole number ratio of atoms of each
element present in a compound
Percentage yield - CORRECT ANSWER-actual yield/theoretical yield x 100
, Atom economy - CORRECT ANSWER-(Molecular mass of desired products/ Molecular mass of all
products) x 100
Electronegativity - CORRECT ANSWER-The power of an atom to attract electron density in a
covalent bond towards itself
electronegativity trend - CORRECT ANSWER-increases across a period, decreases down a group
Enthalpy change - CORRECT ANSWER-Heat energy change measured at constant pressure
Hess's Law - CORRECT ANSWER-The Enthalpy Change for a chemical reaction is independent of
the route taken
Mean bond enthalpy - CORRECT ANSWER-Energy required to break one mole of covalent bonds
between two given atoms, averaged across a range of compounds
Activation energy - CORRECT ANSWER-the minimum energy colliding particles must have in
order to react
dynamic equilibrium - CORRECT ANSWER-Forward and backward reactions take place at same
rate so concentrations of products and reactants remain constant
Only reached in closed system
Le Chatelier's Principle - CORRECT ANSWER-When a system at equilibrium is disturbed, the
equilibrium shifts in the direction that reduces the disturbance
Haber process conditions - CORRECT ANSWER-- 200 atm : high pressures favour forwards
reaction but are costly
- 450°C : low temperature favours towards reaction but rate of reaction too slow at low temps
