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AS-LEVEL AQA CHEMISTRY
QUESTIONS AND VERIFIED
ANSWERS SOLUTIONS
LATEST UPDATE
2024\2025 GRADED A+
"#"How does distance from the nucleus affect ionisation energy? ANSWER The closer the
electron is to the nucleus, the stronger the attraction.
"#"How does shielding affect ionisation energy? ANSWER As the number of electrons
between outer electrons and the nucleus increases, the outer electron feels less attraction towards
the nuclear charge.
,"#"What is the trend in ionisation energy down a group? ANSWER The first ionisation energy
down a group has a general decrease because down a group each element has an extra electron
shell compared to the one above so the extra inner shells will shield the outer electrons from the
nucleus attraction.
"#"What is the trend in ionisation energy across a period? ANSWER The first ionisation energy
across a period has a general increase because it gets harder to remove outer shell electrons.
"#"What is an equation for number of moles involving mass and Mr? ANSWER number of
moles = mass / Mr
"#"What is an equation for number of moles involving concentration and volume? ANSWER
number of moles = concentration x volume
"#"What is an equation for number of particles involving number of moles and Avogadros
constant? ANSWER number of particles = number of moles x Avogadros constant
"#"What is P in regards to the Ideal Gas Equation and what is its units? ANSWER P = nRT / V
pressure and is measured in Pa or Pascals
"#"What is V in regards to the Ideal Gas Equation and what is its units? ANSWER V = nRT / P
volume and is measured in m^3
, "#"What is n in regards to the Ideal Gas Equation? ANSWER n = PV / RT
number of moles
"#"What is R in regards to the Ideal Gas Equation? ANSWER R = 8.31K^-1mol^-1
gas constant
"#"What is T in regards to the Ideal Gas Equation? ANSWER T = temperature and is measured
in K or kelvin ( 273 + Celsius)
"#"What is the equation for percentage atom economy? ANSWER atom economy % = mass of
desired product / total mass of reactants x 100
"#"Why are high atom economy processes better? ANSWER They produce less waste and
make more efficient use of raw materials so are less expensive.
"#"How do you convert m^3 into dm^3? ANSWER x1000
"#"How do you convert dm^3 into cm^3? ANSWER x1000
"#"How do you convert dm^3 into m^3? ANSWER /1000
"#"What is the charge on a sulfate ion (SO4)? ANSWER 2-
AS-LEVEL AQA CHEMISTRY
QUESTIONS AND VERIFIED
ANSWERS SOLUTIONS
LATEST UPDATE
2024\2025 GRADED A+
"#"How does distance from the nucleus affect ionisation energy? ANSWER The closer the
electron is to the nucleus, the stronger the attraction.
"#"How does shielding affect ionisation energy? ANSWER As the number of electrons
between outer electrons and the nucleus increases, the outer electron feels less attraction towards
the nuclear charge.
,"#"What is the trend in ionisation energy down a group? ANSWER The first ionisation energy
down a group has a general decrease because down a group each element has an extra electron
shell compared to the one above so the extra inner shells will shield the outer electrons from the
nucleus attraction.
"#"What is the trend in ionisation energy across a period? ANSWER The first ionisation energy
across a period has a general increase because it gets harder to remove outer shell electrons.
"#"What is an equation for number of moles involving mass and Mr? ANSWER number of
moles = mass / Mr
"#"What is an equation for number of moles involving concentration and volume? ANSWER
number of moles = concentration x volume
"#"What is an equation for number of particles involving number of moles and Avogadros
constant? ANSWER number of particles = number of moles x Avogadros constant
"#"What is P in regards to the Ideal Gas Equation and what is its units? ANSWER P = nRT / V
pressure and is measured in Pa or Pascals
"#"What is V in regards to the Ideal Gas Equation and what is its units? ANSWER V = nRT / P
volume and is measured in m^3
, "#"What is n in regards to the Ideal Gas Equation? ANSWER n = PV / RT
number of moles
"#"What is R in regards to the Ideal Gas Equation? ANSWER R = 8.31K^-1mol^-1
gas constant
"#"What is T in regards to the Ideal Gas Equation? ANSWER T = temperature and is measured
in K or kelvin ( 273 + Celsius)
"#"What is the equation for percentage atom economy? ANSWER atom economy % = mass of
desired product / total mass of reactants x 100
"#"Why are high atom economy processes better? ANSWER They produce less waste and
make more efficient use of raw materials so are less expensive.
"#"How do you convert m^3 into dm^3? ANSWER x1000
"#"How do you convert dm^3 into cm^3? ANSWER x1000
"#"How do you convert dm^3 into m^3? ANSWER /1000
"#"What is the charge on a sulfate ion (SO4)? ANSWER 2-