AQA AS Level
Chemistry Paper 1
LATEST 2025 WITH
QUESTIONS AND
CORRECT
VERIFIED
ANSWERS GRADED
A+ GUARANTEED
PASS
,Describe the chemical properties of two
isotopes of the same element. [2] - ANSWER--
Same chemical properties.
-As same electron configuration.
State the uses of mass spectrometry: [4] -
ANSWER-- Identify elements
- Determine relative molecular mass.
- Determine isotopic mass.
- Determine relative abundance of isotopes.
Why is mass spectrometry done in a vacuum?
[1] - ANSWER-Prevent positive ions from
colliding with molecules in the air.
Describe electrospray ionisation: [4] -
ANSWER-- Sample dissolved in volatile
solvent.
- Injected through a fine hypodermic needle
giving a fine mist/aerosol.
- Tip of needle connected to positive terminal of
a high voltage.
- Each molecule gains a proton as it leaves the
needle.
,Describe acceleration: [2] - ANSWER-- The
positive ions are attracted to a negatively
charged plate and accelerate towards it.
- All ions accelerate forward so that they have
the same kinetic energy, but reach different
velocities due to their varying masses. (lighter
→ faster)
Describe ion drift: [2] - ANSWER-- Some of the
ions pass through a hole in the negatively
charged plate, forming a beam of particles.
They travel along the 'flight tube' towards the
detector.
- As the ions are travelling at different speeds,
they drift apart further.
Describe detection: [2] - ANSWER-- When the
positive ions hit the negatively charged
detection plate, they gain an electron.
- This generates a current, the size of which is
proportional to the number of each type of ion.
Describe data analysis: [1] - ANSWER-The
signal from the detector is passed to a
, computer which generates a mass spectrum
from the current.
What does each peak on the graph represent?
[2] - ANSWER-- Each peak represents different
isotope.
- Height gives relative abundance of each
isotope.
Give the formula for relative atomic mass: [1] -
ANSWER-(sum of abundances not 100)
Describe where electrons are found. [3] -
ANSWER-- Found in shells, orbiting nucleus.
- Within each shell there are sub-shells.
- Within each sub-shell we find orbitals.
Define orbital. [1] - ANSWER-An orbital is a
region within an atom that can hold up to two
electrons with opposite spins.
How many orbitals are there in...
a) an s sub-shell
b) a p sub-shell
c) a d sub-shell [3] - ANSWER-a) one s orbital
Chemistry Paper 1
LATEST 2025 WITH
QUESTIONS AND
CORRECT
VERIFIED
ANSWERS GRADED
A+ GUARANTEED
PASS
,Describe the chemical properties of two
isotopes of the same element. [2] - ANSWER--
Same chemical properties.
-As same electron configuration.
State the uses of mass spectrometry: [4] -
ANSWER-- Identify elements
- Determine relative molecular mass.
- Determine isotopic mass.
- Determine relative abundance of isotopes.
Why is mass spectrometry done in a vacuum?
[1] - ANSWER-Prevent positive ions from
colliding with molecules in the air.
Describe electrospray ionisation: [4] -
ANSWER-- Sample dissolved in volatile
solvent.
- Injected through a fine hypodermic needle
giving a fine mist/aerosol.
- Tip of needle connected to positive terminal of
a high voltage.
- Each molecule gains a proton as it leaves the
needle.
,Describe acceleration: [2] - ANSWER-- The
positive ions are attracted to a negatively
charged plate and accelerate towards it.
- All ions accelerate forward so that they have
the same kinetic energy, but reach different
velocities due to their varying masses. (lighter
→ faster)
Describe ion drift: [2] - ANSWER-- Some of the
ions pass through a hole in the negatively
charged plate, forming a beam of particles.
They travel along the 'flight tube' towards the
detector.
- As the ions are travelling at different speeds,
they drift apart further.
Describe detection: [2] - ANSWER-- When the
positive ions hit the negatively charged
detection plate, they gain an electron.
- This generates a current, the size of which is
proportional to the number of each type of ion.
Describe data analysis: [1] - ANSWER-The
signal from the detector is passed to a
, computer which generates a mass spectrum
from the current.
What does each peak on the graph represent?
[2] - ANSWER-- Each peak represents different
isotope.
- Height gives relative abundance of each
isotope.
Give the formula for relative atomic mass: [1] -
ANSWER-(sum of abundances not 100)
Describe where electrons are found. [3] -
ANSWER-- Found in shells, orbiting nucleus.
- Within each shell there are sub-shells.
- Within each sub-shell we find orbitals.
Define orbital. [1] - ANSWER-An orbital is a
region within an atom that can hold up to two
electrons with opposite spins.
How many orbitals are there in...
a) an s sub-shell
b) a p sub-shell
c) a d sub-shell [3] - ANSWER-a) one s orbital
