AS Level Chemistry A H032/02 Depth in chemistry 2023
(GUARANTEED PASS) NEW EXAMS ACCURATE
SUMMER-FALL SESSION
Nucleons - ANSWER: Protons and neutrons
Electrons (location) - ANSWER: Surrounding the nucleus
Relative mass of an electron - ANSWER: 1/1840
Strong nuclear force - ANSWER: The way protons and neutrons are held together in
the nucleus
Electrostatic forces - ANSWER: The attraction between protons and electrons that
hold them together in the atom
Atomic Number (Z) - ANSWER: The number of protons in the nucleus
Mass number (A) - ANSWER: The total number of protons and neutrons in the
nucleus (the number of nucleons)
Isotope - ANSWER: Same number of protons and electrons, but different number of
neutrons
Mass spectrometer - ANSWER: The most useful instrument for the accurate
determination of relative formula mass
Atomic orbital - ANSWER: A region of space around an atomic nucleus where there is
a high probability of finding an electron
Ionisation energy - ANSWER: The energy required to remove one mole of electrons
from one mole of atoms in the gaseous state
Relative atomic mass (Ar) - ANSWER: The weighted average mass of an atom of an
element, taking into account its naturally occurring isotopes, relative to 1/12 the
relative atomic mass of an atom of carbon-12
Relative molecular mass (Mr) - ANSWER: The mass of that molecule compared to
1/12 the relative atomic mass of an atom of carbon-12
Avogadro constant (the definition) - ANSWER: The number of atoms in 12g of
carbon-12
Avogadro's constant (the number) - ANSWER: 6.022 x 10^23
A mole - ANSWER: The amount of substance that contains 6.022x10^23 particles
,Ideal gas equation - ANSWER: PV=nRT
Empirical formula - ANSWER: The formula that represents the simplest whole
number ratio of the atoms of each element in a compound
Molecular formula - ANSWER: the formula that gives the actual number of atoms of
each element in one molecule of a compound
Stoichiometry - ANSWER: The simple whole number ratios in which chemical species
react
Spectator ions - ANSWER: Ions that are unchanged during a chemical reaction, that
is, they do not take part in the reaction
Atom economy - ANSWER: Describes the efficiency of a chemical reaction by
comparing the total number of atoms in the product with the total number of atoms
in the starting materials
Percentage yield - ANSWER: The practical efficiency of the process
Ionic bonding - ANSWER: A chemical bond between metals and non-metals where
electrons are transferred from the metal to the non-metal to form 2 oppositely
charged ions that form electrostatic forces between them
Covalent bonding - ANSWER: A chemical bond between non-metal atoms where a
pair of electrons is shared
Lattice - ANSWER: A regular 3D arrangement of atoms, ions or molecules
Co-ordinate bond - ANSWER: Where both electrons come from one of the atoms in a
covalent bond
Dative covalent bond - ANSWER: Where both electrons come from one of the atoms
in a covalent bond
Lone pair - ANSWER: A pair of electrons in the outer shell of an electron that isn't
involved in a bond
Metallic bonding - ANSWER: A chemical bond between metals where outer electrons
are delocalised within the lattice of metal ions
Electronegativity - ANSWER: The power of an atom to attract the electron density in
a covalent bond towards itself
Electron density - ANSWER: The probability of electrons being found in a particular
volume of space
, Polarity - ANSWER: The unequal sharing of the electrons between atoms in a
covalent bond
Polar - ANSWER: Describes a molecule where the charge is not equally distributed,
one end is more positive, the other more negative
Dipole-dipole forces - ANSWER: An intermolecular force between two molecules
with permanent dipoles
van der Waals forces - ANSWER: An intermolecular force between all atoms and
molecules caused by instantaneous dipoles which form very weak electrostatic
attractions
Hydrogen bonding - ANSWER: An intermolecular force between a slightly positive
hydrogen atom and a much more electronegative atom which forms a strong
interaction
Electron pair repulsion theory - ANSWER: Suggests that the electrons surrounding
the central atom in the atoms repel each other, therefore the atoms form a shape
where they are furthest away from each other
Linear - ANSWER: 2 pairs of electrons shape
180 - ANSWER: 2 pairs of electrons bond angle
Trigonal planar - ANSWER: 3 pairs of electrons shape
120 - ANSWER: 3 pairs of electrons bond angle
Tetrahedral - ANSWER: 4 pairs of electrons shape
109.5 - ANSWER: 4 pairs of electrons bond angle
Trigonal bipyramid - ANSWER: 5 pairs of electrons shape
120 - ANSWER: 5 pairs of electrons bond angle
Octahedral - ANSWER: 6 pairs of electrons shape
90 - ANSWER: 6 pairs of electrons bond angle
-2 - ANSWER: Effect of one lone pair on bond angle
Enthalpy change - ANSWER: The heat energy change measured under constant
pressure whilst temperature depends on the average kinetic energy of the particles
(GUARANTEED PASS) NEW EXAMS ACCURATE
SUMMER-FALL SESSION
Nucleons - ANSWER: Protons and neutrons
Electrons (location) - ANSWER: Surrounding the nucleus
Relative mass of an electron - ANSWER: 1/1840
Strong nuclear force - ANSWER: The way protons and neutrons are held together in
the nucleus
Electrostatic forces - ANSWER: The attraction between protons and electrons that
hold them together in the atom
Atomic Number (Z) - ANSWER: The number of protons in the nucleus
Mass number (A) - ANSWER: The total number of protons and neutrons in the
nucleus (the number of nucleons)
Isotope - ANSWER: Same number of protons and electrons, but different number of
neutrons
Mass spectrometer - ANSWER: The most useful instrument for the accurate
determination of relative formula mass
Atomic orbital - ANSWER: A region of space around an atomic nucleus where there is
a high probability of finding an electron
Ionisation energy - ANSWER: The energy required to remove one mole of electrons
from one mole of atoms in the gaseous state
Relative atomic mass (Ar) - ANSWER: The weighted average mass of an atom of an
element, taking into account its naturally occurring isotopes, relative to 1/12 the
relative atomic mass of an atom of carbon-12
Relative molecular mass (Mr) - ANSWER: The mass of that molecule compared to
1/12 the relative atomic mass of an atom of carbon-12
Avogadro constant (the definition) - ANSWER: The number of atoms in 12g of
carbon-12
Avogadro's constant (the number) - ANSWER: 6.022 x 10^23
A mole - ANSWER: The amount of substance that contains 6.022x10^23 particles
,Ideal gas equation - ANSWER: PV=nRT
Empirical formula - ANSWER: The formula that represents the simplest whole
number ratio of the atoms of each element in a compound
Molecular formula - ANSWER: the formula that gives the actual number of atoms of
each element in one molecule of a compound
Stoichiometry - ANSWER: The simple whole number ratios in which chemical species
react
Spectator ions - ANSWER: Ions that are unchanged during a chemical reaction, that
is, they do not take part in the reaction
Atom economy - ANSWER: Describes the efficiency of a chemical reaction by
comparing the total number of atoms in the product with the total number of atoms
in the starting materials
Percentage yield - ANSWER: The practical efficiency of the process
Ionic bonding - ANSWER: A chemical bond between metals and non-metals where
electrons are transferred from the metal to the non-metal to form 2 oppositely
charged ions that form electrostatic forces between them
Covalent bonding - ANSWER: A chemical bond between non-metal atoms where a
pair of electrons is shared
Lattice - ANSWER: A regular 3D arrangement of atoms, ions or molecules
Co-ordinate bond - ANSWER: Where both electrons come from one of the atoms in a
covalent bond
Dative covalent bond - ANSWER: Where both electrons come from one of the atoms
in a covalent bond
Lone pair - ANSWER: A pair of electrons in the outer shell of an electron that isn't
involved in a bond
Metallic bonding - ANSWER: A chemical bond between metals where outer electrons
are delocalised within the lattice of metal ions
Electronegativity - ANSWER: The power of an atom to attract the electron density in
a covalent bond towards itself
Electron density - ANSWER: The probability of electrons being found in a particular
volume of space
, Polarity - ANSWER: The unequal sharing of the electrons between atoms in a
covalent bond
Polar - ANSWER: Describes a molecule where the charge is not equally distributed,
one end is more positive, the other more negative
Dipole-dipole forces - ANSWER: An intermolecular force between two molecules
with permanent dipoles
van der Waals forces - ANSWER: An intermolecular force between all atoms and
molecules caused by instantaneous dipoles which form very weak electrostatic
attractions
Hydrogen bonding - ANSWER: An intermolecular force between a slightly positive
hydrogen atom and a much more electronegative atom which forms a strong
interaction
Electron pair repulsion theory - ANSWER: Suggests that the electrons surrounding
the central atom in the atoms repel each other, therefore the atoms form a shape
where they are furthest away from each other
Linear - ANSWER: 2 pairs of electrons shape
180 - ANSWER: 2 pairs of electrons bond angle
Trigonal planar - ANSWER: 3 pairs of electrons shape
120 - ANSWER: 3 pairs of electrons bond angle
Tetrahedral - ANSWER: 4 pairs of electrons shape
109.5 - ANSWER: 4 pairs of electrons bond angle
Trigonal bipyramid - ANSWER: 5 pairs of electrons shape
120 - ANSWER: 5 pairs of electrons bond angle
Octahedral - ANSWER: 6 pairs of electrons shape
90 - ANSWER: 6 pairs of electrons bond angle
-2 - ANSWER: Effect of one lone pair on bond angle
Enthalpy change - ANSWER: The heat energy change measured under constant
pressure whilst temperature depends on the average kinetic energy of the particles
