AS-level AQA Chemistry Exam Prep Questions
with Complete Solutions Latest Update
2024
Linear molecule - ANSWER 2 bonds 180 degree angles 2D e.g: CO2
Trigonal planar molecule - ANSWER 3 bonds 120 degree angles 2D e.g: BF3
Tetrahedral molecule - ANSWER 4 bonds 109.5 degree angles 3D e.g: CH4
Trigonal bipyramid molecule - ANSWER 5 bonds 120 degree and 90 degree angles 3D e.g.: PCl5
Octahedral molecule - ANSWER 6 bonds 90 degree angles 3D e.g.: SF6
Lone pairs - ANSWER Cause a repulsion of 2.5 degrees.
Charge Clouds - ANSWER What bonding pairs and lone pairs exist as in a molecule.
Largest repulsion angle in a molecule - ANSWER lone pair - lone pair
2nd largest repulsion angle in a molecule - ANSWER lone pair - bonding pair
Smallest repulsion angle in a molecule - ANSWER bonding pair - bonding pair
Electronegativity - ANSWER An atoms ability to attract the electron pair in a covalent bond
, Polar - ANSWER caused by the difference in electronegativity in a covalent bond, where the electrons
are pulled towards the more electronegative atom creating a dipole.
Dipole - ANSWER difference in charge between atoms created by a shift in electron density within
the bond.
Permanent dipole- dipole forces - ANSWER weak electrostatic forces of attraction between polar
molecules S- and S+ charges in their permanent dipoles.
Van der Waals - ANSWER The weakest intermolecular force formed between all atoms and molecules
when temporary dipoles are formed and attracted (due to fast electron movement in charge clouds)
Hydrogen bonds - ANSWER Hydrogen covalently bonded to fluorine, nitrogen and oxygen. H atoms
form bonds with lone pairs. High boiling and melting points.
Metallic bonding - ANSWER postive metal ions attracted to seas of negative delocalised electrons to
form a regular lattice. HMP and HBP, conduct electricity.
Enthalpy change - ANSWER heat energy transferred in a reaction at constant pressure. Kjmol-1
Standard enthalpy of formation - ANSWER the enthalpy change when 1 mole of a compound is
formed from its elements in their standard states under standard conditions
Standard enthalpy of combustion - ANSWER the enthalpy change when 1 mole of a substance is
completely burned in oxygen under standard conditions.
Enthalpy - ANSWER The heat content that is stored in a chemical system. q=mcDELTAt
Exothermic reactions - ANSWER DeltaH is negative, gives out energy, temperature decrease, forms
bonds e.g. oxidation... combustion of fuel, oxidation of glucose carbohydrates
with Complete Solutions Latest Update
2024
Linear molecule - ANSWER 2 bonds 180 degree angles 2D e.g: CO2
Trigonal planar molecule - ANSWER 3 bonds 120 degree angles 2D e.g: BF3
Tetrahedral molecule - ANSWER 4 bonds 109.5 degree angles 3D e.g: CH4
Trigonal bipyramid molecule - ANSWER 5 bonds 120 degree and 90 degree angles 3D e.g.: PCl5
Octahedral molecule - ANSWER 6 bonds 90 degree angles 3D e.g.: SF6
Lone pairs - ANSWER Cause a repulsion of 2.5 degrees.
Charge Clouds - ANSWER What bonding pairs and lone pairs exist as in a molecule.
Largest repulsion angle in a molecule - ANSWER lone pair - lone pair
2nd largest repulsion angle in a molecule - ANSWER lone pair - bonding pair
Smallest repulsion angle in a molecule - ANSWER bonding pair - bonding pair
Electronegativity - ANSWER An atoms ability to attract the electron pair in a covalent bond
, Polar - ANSWER caused by the difference in electronegativity in a covalent bond, where the electrons
are pulled towards the more electronegative atom creating a dipole.
Dipole - ANSWER difference in charge between atoms created by a shift in electron density within
the bond.
Permanent dipole- dipole forces - ANSWER weak electrostatic forces of attraction between polar
molecules S- and S+ charges in their permanent dipoles.
Van der Waals - ANSWER The weakest intermolecular force formed between all atoms and molecules
when temporary dipoles are formed and attracted (due to fast electron movement in charge clouds)
Hydrogen bonds - ANSWER Hydrogen covalently bonded to fluorine, nitrogen and oxygen. H atoms
form bonds with lone pairs. High boiling and melting points.
Metallic bonding - ANSWER postive metal ions attracted to seas of negative delocalised electrons to
form a regular lattice. HMP and HBP, conduct electricity.
Enthalpy change - ANSWER heat energy transferred in a reaction at constant pressure. Kjmol-1
Standard enthalpy of formation - ANSWER the enthalpy change when 1 mole of a compound is
formed from its elements in their standard states under standard conditions
Standard enthalpy of combustion - ANSWER the enthalpy change when 1 mole of a substance is
completely burned in oxygen under standard conditions.
Enthalpy - ANSWER The heat content that is stored in a chemical system. q=mcDELTAt
Exothermic reactions - ANSWER DeltaH is negative, gives out energy, temperature decrease, forms
bonds e.g. oxidation... combustion of fuel, oxidation of glucose carbohydrates
