AQA AS Chemistry 7404/2 Paper 2 June 2024 Question
Paper & Mark Scheme STUDY BUNDLE PACKAGE WITH
SOLUTIONS
Nucleons - ANSWERProtons and neutrons
Electrons (location) - ANSWERSurrounding the nucleus
Relative mass of an electron - ANSWER1/1840
Strong nuclear force - ANSWERThe way protons and neutrons are held together in
the nucleus
Electrostatic forces - ANSWERThe attraction between protons and electrons that
hold them together in the atom
Atomic Number (Z) - ANSWERThe number of protons in the nucleus
Mass number (A) - ANSWERThe total number of protons and neutrons in the nucleus
(the number of nucleons)
Isotope - ANSWERSame number of protons and electrons, but different number of
neutrons
Mass spectrometer - ANSWERThe most useful instrument for the accurate
determination of relative formula mass
Atomic orbital - ANSWERA region of space around an atomic nucleus where there is
a high probability of finding an electron
Ionisation energy - ANSWERThe energy required to remove one mole of electrons
from one mole of atoms in the gaseous state
Relative atomic mass (Ar) - ANSWERThe 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) - ANSWERThe mass of that molecule compared to 1/12
the relative atomic mass of an atom of carbon-12
Avogadro constant (the definition) - ANSWERThe number of atoms in 12g of carbon-
12
Avogadro's constant (the number) - ANSWER6.022 x 10^23
A mole - ANSWERThe amount of substance that contains 6.022x10^23 particles
,Ideal gas equation - ANSWERPV=nRT
Empirical formula - ANSWERThe formula that represents the simplest whole number
ratio of the atoms of each element in a compound
Molecular formula - ANSWERthe formula that gives the actual number of atoms of
each element in one molecule of a compound
Stoichiometry - ANSWERThe simple whole number ratios in which chemical species
react
Spectator ions - ANSWERIons that are unchanged during a chemical reaction, that is,
they do not take part in the reaction
Atom economy - ANSWERDescribes 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 - ANSWERThe practical efficiency of the process
Ionic bonding - ANSWERA 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 - ANSWERA chemical bond between non-metal atoms where a pair
of electrons is shared
Lattice - ANSWERA regular 3D arrangement of atoms, ions or molecules
Co-ordinate bond - ANSWERWhere both electrons come from one of the atoms in a
covalent bond
Dative covalent bond - ANSWERWhere both electrons come from one of the atoms
in a covalent bond
Lone pair - ANSWERA pair of electrons in the outer shell of an electron that isn't
involved in a bond
Metallic bonding - ANSWERA chemical bond between metals where outer electrons
are delocalised within the lattice of metal ions
Electronegativity - ANSWERThe power of an atom to attract the electron density in a
covalent bond towards itself
Electron density - ANSWERThe probability of electrons being found in a particular
volume of space
, Polarity - ANSWERThe unequal sharing of the electrons between atoms in a covalent
bond
Polar - ANSWERDescribes a molecule where the charge is not equally distributed,
one end is more positive, the other more negative
Dipole-dipole forces - ANSWERAn intermolecular force between two molecules with
permanent dipoles
van der Waals forces - ANSWERAn intermolecular force between all atoms and
molecules caused by instantaneous dipoles which form very weak electrostatic
attractions
Hydrogen bonding - ANSWERAn intermolecular force between a slightly positive
hydrogen atom and a much more electronegative atom which forms a strong
interaction
Electron pair repulsion theory - ANSWERSuggests 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 - ANSWER2 pairs of electrons shape
180 - ANSWER2 pairs of electrons bond angle
Trigonal planar - ANSWER3 pairs of electrons shape
120 - ANSWER3 pairs of electrons bond angle
Tetrahedral - ANSWER4 pairs of electrons shape
109.5 - ANSWER4 pairs of electrons bond angle
Trigonal bipyramid - ANSWER5 pairs of electrons shape
120 - ANSWER5 pairs of electrons bond angle
Octahedral - ANSWER6 pairs of electrons shape
90 - ANSWER6 pairs of electrons bond angle
-2 - ANSWEREffect of one lone pair on bond angle
Enthalpy change - ANSWERThe heat energy change measured under constant
pressure whilst temperature depends on the average kinetic energy of the particles
Paper & Mark Scheme STUDY BUNDLE PACKAGE WITH
SOLUTIONS
Nucleons - ANSWERProtons and neutrons
Electrons (location) - ANSWERSurrounding the nucleus
Relative mass of an electron - ANSWER1/1840
Strong nuclear force - ANSWERThe way protons and neutrons are held together in
the nucleus
Electrostatic forces - ANSWERThe attraction between protons and electrons that
hold them together in the atom
Atomic Number (Z) - ANSWERThe number of protons in the nucleus
Mass number (A) - ANSWERThe total number of protons and neutrons in the nucleus
(the number of nucleons)
Isotope - ANSWERSame number of protons and electrons, but different number of
neutrons
Mass spectrometer - ANSWERThe most useful instrument for the accurate
determination of relative formula mass
Atomic orbital - ANSWERA region of space around an atomic nucleus where there is
a high probability of finding an electron
Ionisation energy - ANSWERThe energy required to remove one mole of electrons
from one mole of atoms in the gaseous state
Relative atomic mass (Ar) - ANSWERThe 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) - ANSWERThe mass of that molecule compared to 1/12
the relative atomic mass of an atom of carbon-12
Avogadro constant (the definition) - ANSWERThe number of atoms in 12g of carbon-
12
Avogadro's constant (the number) - ANSWER6.022 x 10^23
A mole - ANSWERThe amount of substance that contains 6.022x10^23 particles
,Ideal gas equation - ANSWERPV=nRT
Empirical formula - ANSWERThe formula that represents the simplest whole number
ratio of the atoms of each element in a compound
Molecular formula - ANSWERthe formula that gives the actual number of atoms of
each element in one molecule of a compound
Stoichiometry - ANSWERThe simple whole number ratios in which chemical species
react
Spectator ions - ANSWERIons that are unchanged during a chemical reaction, that is,
they do not take part in the reaction
Atom economy - ANSWERDescribes 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 - ANSWERThe practical efficiency of the process
Ionic bonding - ANSWERA 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 - ANSWERA chemical bond between non-metal atoms where a pair
of electrons is shared
Lattice - ANSWERA regular 3D arrangement of atoms, ions or molecules
Co-ordinate bond - ANSWERWhere both electrons come from one of the atoms in a
covalent bond
Dative covalent bond - ANSWERWhere both electrons come from one of the atoms
in a covalent bond
Lone pair - ANSWERA pair of electrons in the outer shell of an electron that isn't
involved in a bond
Metallic bonding - ANSWERA chemical bond between metals where outer electrons
are delocalised within the lattice of metal ions
Electronegativity - ANSWERThe power of an atom to attract the electron density in a
covalent bond towards itself
Electron density - ANSWERThe probability of electrons being found in a particular
volume of space
, Polarity - ANSWERThe unequal sharing of the electrons between atoms in a covalent
bond
Polar - ANSWERDescribes a molecule where the charge is not equally distributed,
one end is more positive, the other more negative
Dipole-dipole forces - ANSWERAn intermolecular force between two molecules with
permanent dipoles
van der Waals forces - ANSWERAn intermolecular force between all atoms and
molecules caused by instantaneous dipoles which form very weak electrostatic
attractions
Hydrogen bonding - ANSWERAn intermolecular force between a slightly positive
hydrogen atom and a much more electronegative atom which forms a strong
interaction
Electron pair repulsion theory - ANSWERSuggests 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 - ANSWER2 pairs of electrons shape
180 - ANSWER2 pairs of electrons bond angle
Trigonal planar - ANSWER3 pairs of electrons shape
120 - ANSWER3 pairs of electrons bond angle
Tetrahedral - ANSWER4 pairs of electrons shape
109.5 - ANSWER4 pairs of electrons bond angle
Trigonal bipyramid - ANSWER5 pairs of electrons shape
120 - ANSWER5 pairs of electrons bond angle
Octahedral - ANSWER6 pairs of electrons shape
90 - ANSWER6 pairs of electrons bond angle
-2 - ANSWEREffect of one lone pair on bond angle
Enthalpy change - ANSWERThe heat energy change measured under constant
pressure whilst temperature depends on the average kinetic energy of the particles
