AQA AS CHEMISTRY 7404 2 PAPER 2
EXAMINATION TEST 2026 ORGANIC AND
PHYSICAL CHEMISTRY MARK SCHEME
⩥ Atomic number. Answer: Numbers of protons in the nucleus and
number of electrons in shells.
⩥ Negative Ions. Answer: More electrons than protons.
⩥ Positive ions. Answer: More protons than electrons.
⩥ Relative isotopic mass. Answer: mass of an atom of an isotope of an
element on a scale where an atom of carbon12 is 12.
⩥ Relative atomic mass. Answer: average mass of an atom of an element
on a scale where an atom of carbon12 is 12.
⩥ Relative molecular mass. Answer: average mass of a molecule on a
scale where an atom of carbon12 is 12.
⩥ First ionisation energy. Answer: the energy needed too remove 1
electron from each atom in 1 mole of gaseous atoms to form 1 mole of
gaseous 1+ ions.
,⩥ Second ionisation energy. Answer: the energy needed to remove 1
electron from each ion in 1 mole of gaseous 1+ ions to form 1 mole of
gaseous 2+ ions.
⩥ Number of particles=. Answer: Number of moles x Avagadros
constant (6.02 x 10^23)
⩥ Number of moles=. Answer: Mass / Mr
⩥ Number of moles=. Answer: Concentration (moldm^-3) x Volume
(dm^3)
⩥ Methyl orange indicator. Answer: yellow in acid, red in alkali.
Commonly used in titrations.
⩥ Phenolphthalein indicator. Answer: pink in alkali, colourless in acid.
Commonly used in titrations.
⩥ Avogadros constant. Answer: the number of atoms in 12g of carbon12
(6.02 x 10^23)
⩥ Ideal gas equation. Answer: Pv= nRT
, ⩥ Empirical formula. Answer: simplest whole number ratio of atoms of
each element in a compound.
⩥ Molecular formula. Answer: gives the actual numbers of each element
in a molecule.
⩥ Percentage yield. Answer: how much product was actually made
compared with the amount of product that was expected
⩥ theoretical yield. Answer: the maximum mass of product expected in a
reaction.
⩥ actual yield. Answer: the mass of product that is actually obtained in a
reaction.
⩥ Atom economy. Answer: measure of the efficiency of a chemical
reaction. The proportional mass of reactants that actually become part of
the desired product in a balanced chemical equation.
⩥ Ionic bonding. Answer: Ions (metal and non metal) are held together
by electrostatic forces of attraction due to the transferring of electrons.
Eg: Sodium chloride.
EXAMINATION TEST 2026 ORGANIC AND
PHYSICAL CHEMISTRY MARK SCHEME
⩥ Atomic number. Answer: Numbers of protons in the nucleus and
number of electrons in shells.
⩥ Negative Ions. Answer: More electrons than protons.
⩥ Positive ions. Answer: More protons than electrons.
⩥ Relative isotopic mass. Answer: mass of an atom of an isotope of an
element on a scale where an atom of carbon12 is 12.
⩥ Relative atomic mass. Answer: average mass of an atom of an element
on a scale where an atom of carbon12 is 12.
⩥ Relative molecular mass. Answer: average mass of a molecule on a
scale where an atom of carbon12 is 12.
⩥ First ionisation energy. Answer: the energy needed too remove 1
electron from each atom in 1 mole of gaseous atoms to form 1 mole of
gaseous 1+ ions.
,⩥ Second ionisation energy. Answer: the energy needed to remove 1
electron from each ion in 1 mole of gaseous 1+ ions to form 1 mole of
gaseous 2+ ions.
⩥ Number of particles=. Answer: Number of moles x Avagadros
constant (6.02 x 10^23)
⩥ Number of moles=. Answer: Mass / Mr
⩥ Number of moles=. Answer: Concentration (moldm^-3) x Volume
(dm^3)
⩥ Methyl orange indicator. Answer: yellow in acid, red in alkali.
Commonly used in titrations.
⩥ Phenolphthalein indicator. Answer: pink in alkali, colourless in acid.
Commonly used in titrations.
⩥ Avogadros constant. Answer: the number of atoms in 12g of carbon12
(6.02 x 10^23)
⩥ Ideal gas equation. Answer: Pv= nRT
, ⩥ Empirical formula. Answer: simplest whole number ratio of atoms of
each element in a compound.
⩥ Molecular formula. Answer: gives the actual numbers of each element
in a molecule.
⩥ Percentage yield. Answer: how much product was actually made
compared with the amount of product that was expected
⩥ theoretical yield. Answer: the maximum mass of product expected in a
reaction.
⩥ actual yield. Answer: the mass of product that is actually obtained in a
reaction.
⩥ Atom economy. Answer: measure of the efficiency of a chemical
reaction. The proportional mass of reactants that actually become part of
the desired product in a balanced chemical equation.
⩥ Ionic bonding. Answer: Ions (metal and non metal) are held together
by electrostatic forces of attraction due to the transferring of electrons.
Eg: Sodium chloride.
