AQA AS LEVEL CHEMISTRY PAPER 1 LATEST 2025 WITH QUESTIONS AND CORRECT VERIFIED
ANSWERS GRADED A+ GUARANTEED PASS
What is the charge of a proton? - (ANSWER)+1
What is the charge of a neutron? - (ANSWER)0
What is the charge of an electron? - (ANSWER)-1
What is the mass of a proton? - (ANSWER)1
What is the mass of a neutron? - (ANSWER)1
What is the mass of an electron? - (ANSWER)1/1800
What is an isotope? - (ANSWER)Isotopes of an element are atoms with the same number of protons but
different numbers of neutrons.
Why do isotopes of an element all have the same chemical properties? - (ANSWER)This is because
chemical properties are decided by the number and arrangements of electrons and all isotopes of an
element have the same number of electrons.
Why do isotopes of an element have different physical properties? - (ANSWER)This is because physical
properties are decided by the mass number and isotopes of an element have different mass numbers.
What is the first stage in time of flight mass spectrometry and what are the 2 ways it can occur? -
(ANSWER)1. Electron spray ionisation
2.Electron impact ionisation
What is electron spray ionisation? - (ANSWER)The sample is dissolved and pushed through a small
nozzle at high pressure. A high voltage is applied to it causing each particle to gain a + ion so that the gas
is made up of positive ions.
1
, AQA AS LEVEL CHEMISTRY PAPER 1 LATEST 2025 WITH QUESTIONS AND CORRECT VERIFIED
ANSWERS GRADED A+ GUARANTEED PASS
What is electron impact ionisation? - (ANSWER)The sample is vaporised and an electron gun is used to
fire high energy electrons which knocks of 1 electron of each particle so they become positive ions.
What is the second stage in time of flight mass spectrometry? - (ANSWER)Acceleration
What happens in the acceleration stage of time of flight mass spectrometry? - (ANSWER)The positively
charged ions are accelerated by an electric field so that they all have the same kinetic energy which
means that the lighter ions will move faster than the heavier ions.
What is the third stage in time of flight mass spectrometry? - (ANSWER)Ion drift
What happens in the ion drift stage of time of flight mass spectrometry? - (ANSWER)The ions enter a
region with no electric field, so they just drift through it. Lighter ions will drift through faster than
heavier ions.
What is the final stage of time of flight mass spectrometry? - (ANSWER)Detection
What happens in the detection stage of time of flight mass spectrometry? - (ANSWER)Because ions have
a lower mass/charge ratio travel at a higher speed in the drift region, they reach the detector in less
time than ions with a higher mass/charge ratio. The detector detects charged particles and a mass
spectrum is produced.
What is the electronic configuration of calcium? - (ANSWER)1s2,2s2,2p6,3s2,3p6,4s2
What is the electronic configuration of chromium? - (ANSWER)1s2,2s2,2p6,3s2,3p6,3d5,4s1
What is the first ionisation energy? - (ANSWER)The first ionisation energy needed to remove one
electron from each atom in 1 mole of gaseous atoms to form 1 mole of +1 gaseous ion..
2
, AQA AS LEVEL CHEMISTRY PAPER 1 LATEST 2025 WITH QUESTIONS AND CORRECT VERIFIED
ANSWERS GRADED A+ GUARANTEED PASS
How does nuclear charge affect ionisation energy? - (ANSWER)More protons means more positively
charged means the stronger the attraction for electrons.
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 the definition of relative atomic mass (Ar)? - (ANSWER)The relative atomic mass is the average
mass of an atom of an element on a scale where an atom of carbon-12 is 12.
What is the definition of relative molecular mass (Mr)? - (ANSWER)The relative molecular mass is the
average mass of a molecule on a scale where an atom of carbon-12 is 12.
What is the Avogadros Constant? - (ANSWER)The number of particles in a mole which is equivalent to
6.02 x 10^23.
What is an equation for number of moles involving mass and Mr? - (ANSWER)number of moles = mass /
Mr
3
ANSWERS GRADED A+ GUARANTEED PASS
What is the charge of a proton? - (ANSWER)+1
What is the charge of a neutron? - (ANSWER)0
What is the charge of an electron? - (ANSWER)-1
What is the mass of a proton? - (ANSWER)1
What is the mass of a neutron? - (ANSWER)1
What is the mass of an electron? - (ANSWER)1/1800
What is an isotope? - (ANSWER)Isotopes of an element are atoms with the same number of protons but
different numbers of neutrons.
Why do isotopes of an element all have the same chemical properties? - (ANSWER)This is because
chemical properties are decided by the number and arrangements of electrons and all isotopes of an
element have the same number of electrons.
Why do isotopes of an element have different physical properties? - (ANSWER)This is because physical
properties are decided by the mass number and isotopes of an element have different mass numbers.
What is the first stage in time of flight mass spectrometry and what are the 2 ways it can occur? -
(ANSWER)1. Electron spray ionisation
2.Electron impact ionisation
What is electron spray ionisation? - (ANSWER)The sample is dissolved and pushed through a small
nozzle at high pressure. A high voltage is applied to it causing each particle to gain a + ion so that the gas
is made up of positive ions.
1
, AQA AS LEVEL CHEMISTRY PAPER 1 LATEST 2025 WITH QUESTIONS AND CORRECT VERIFIED
ANSWERS GRADED A+ GUARANTEED PASS
What is electron impact ionisation? - (ANSWER)The sample is vaporised and an electron gun is used to
fire high energy electrons which knocks of 1 electron of each particle so they become positive ions.
What is the second stage in time of flight mass spectrometry? - (ANSWER)Acceleration
What happens in the acceleration stage of time of flight mass spectrometry? - (ANSWER)The positively
charged ions are accelerated by an electric field so that they all have the same kinetic energy which
means that the lighter ions will move faster than the heavier ions.
What is the third stage in time of flight mass spectrometry? - (ANSWER)Ion drift
What happens in the ion drift stage of time of flight mass spectrometry? - (ANSWER)The ions enter a
region with no electric field, so they just drift through it. Lighter ions will drift through faster than
heavier ions.
What is the final stage of time of flight mass spectrometry? - (ANSWER)Detection
What happens in the detection stage of time of flight mass spectrometry? - (ANSWER)Because ions have
a lower mass/charge ratio travel at a higher speed in the drift region, they reach the detector in less
time than ions with a higher mass/charge ratio. The detector detects charged particles and a mass
spectrum is produced.
What is the electronic configuration of calcium? - (ANSWER)1s2,2s2,2p6,3s2,3p6,4s2
What is the electronic configuration of chromium? - (ANSWER)1s2,2s2,2p6,3s2,3p6,3d5,4s1
What is the first ionisation energy? - (ANSWER)The first ionisation energy needed to remove one
electron from each atom in 1 mole of gaseous atoms to form 1 mole of +1 gaseous ion..
2
, AQA AS LEVEL CHEMISTRY PAPER 1 LATEST 2025 WITH QUESTIONS AND CORRECT VERIFIED
ANSWERS GRADED A+ GUARANTEED PASS
How does nuclear charge affect ionisation energy? - (ANSWER)More protons means more positively
charged means the stronger the attraction for electrons.
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 the definition of relative atomic mass (Ar)? - (ANSWER)The relative atomic mass is the average
mass of an atom of an element on a scale where an atom of carbon-12 is 12.
What is the definition of relative molecular mass (Mr)? - (ANSWER)The relative molecular mass is the
average mass of a molecule on a scale where an atom of carbon-12 is 12.
What is the Avogadros Constant? - (ANSWER)The number of particles in a mole which is equivalent to
6.02 x 10^23.
What is an equation for number of moles involving mass and Mr? - (ANSWER)number of moles = mass /
Mr
3
