Edexcel A level chemistry paper 1 All
Topics Comprehensive 2024 Exam Quiz
Study Guide
Atoms - Answer>>Made up of 3 subatomic particles - electrons,
neutrons and protons
Electrons - Answer>>- Subatomic particle
- Charge of -1
- Arranged in orbitals
- Relative mass of 0.0005 - negligible
Nucleus - Answer>>- Where most of the mass of the atom is
contained
- Made up of protons and neutrons
- Diameter is much smaller than that of whole atom
Neutrons - Answer>>- Subatomic particle
- No charge
- Relative mass of 1
- Contained in nucleus
- Dictates the isotope of an element that an atom is; not all atoms
of the same element have the same number of neutrons
Protons - Answer>>- Subatomic particle
- Charge of +1
- Relative mass of 1
- Contained in nucleus
- Dictates the type of element that an atom is; all atoms of the
same element have the same number of protons
Ions - Answer>>- Ions are charged atoms; positive ions have
more protons than electrons, and vice versa for negative ions
,- Ions have different numbers of electrons to their parent
elements'
- e.g. Li⁺ has only 2 electrons, whereas Li has 3
- e.g. F has 9 electrons, F⁻ has 10
Isotopes - Answer>>- Isotopes of an element are atoms with the
same number of protons but a different number of neutrons.
- E.g. ³⁵Cl has 18 neutrons and ³⁷Cl has 20
- Number and arrangement of electrons dictate the chemical
properties of an element, so all isotopes of an element have the
same chemical properties
- However isotopes of the same element can have different
physical properties such as density and diffusion rates
Relative atomic mass - Answer>>The relative atomic mass is
the weighted mean mass of an atom of an element compared to
1/12th of the mass of an atom of carbon-12
Can be worked out from Isotopic Abundances - Multiply the
isotopic mass of each isotope by its % abundance, add them up
then divide the total by 100
Relative isotopic mass - Answer>>The mass of an atom of an
isotope of an element compared with 1/12th if the mass of an
atom of carbon-12
Relative molecular/formula mass - Answer>>The average mass
of a molecule compared to the mass of an atom of carbon-12
Mass Spectrometry - Answer>>Can be used to work out the
relative atomic mass. Particles measured with a mass
spectrometer must be charged, so they are often bombarded with
electrons in order to remove one, giving a charge of +1
,1. Multiply each relative isotopic mass by its relative isotopic
abundance, and add up the results
2. Divide by the sum of the isotopic abundances
Calculating Isotopic Masses from Relative atomic mass -
Answer>>Need: Relative mass of element and all but one of the
abundances and isotopic masses of its isotopes
1. Find abundance of last isotope; percentage abundances so do
100-(sum of known% abundances)
2. Put into equation for finding the relative atomic mass and
rearrange for the unknown value
Predicting mass spectra for diatomic molecules (E.g. Cl₂) -
Answer>>1. Express each % as a decimal (e.g. 75%→0.75 and
25%→0.25)
2. Make a table showing all the different Cl₂ molecules. For each,
multiply the abundances of each isotope to get the relative
abundance of each molecule.
3. Look for any values in the table that are the same and add up
their abundances
4. Divide all the relative abundances by the smallest relative
abundance to get the smallest whole number ratio. And by
working out the relative molecular mass of each molecule, you
can predict the mass spectra
5. Plot the mass spectra with the relative abundances you worked
out on the y-axis and the relative molecular masses (m/z) on the
x-axis
Identifying compounds using mass spectrometry - Answer>>1.
Molecules in a sample are bombarded with electrons to remove
an electron and form a molecular ion, M⁺
2. The molecular mass is shown by the molecular ion peak - the
peak with the highest m/z value, not including any M+1 peaks
caused by presence of carbon-13
, Electron Shells - Answer>>- Made up of subshells and orbitals
- Electrons move around the nucleus in quantum shells (aka
energy levels)
- Shells further from the nucleus have a greater energy level than
those closer to the nucleus
- Shells contain different types of subshell, each of which have
different numbers of orbitals which can each hold 2 electrons
Subshells - Answer>>This table shows the subshells and how
many electrons can be contained in each.
Orbitals - Answer>>- Orbitals within the same subshell have the
same energy
- s-orbitals are spherical
- p-orbitals are dumbbell-shaped. There are 3 p-orbitals and they
are at right angles to each other
Electronic configuration - Answer>>- Electrons fill up the lowest
energy subshells first
- Electrons fill orbitals singly before they start pairing up
- Exceptions: Chromium and Copper - donate a 4s electron to the
3d subshell because they are more stable with a full or half-full d-
subshell
Periodic table electron configuration blocks - Answer>>- s-block
elements have an outer shell electronic configuration of s¹ or s²
- p-block elements have an outer shell electronic configuration of
s²p¹ to s²p⁶
Atomic emission spectra - electron excitement - Answer>>-
Electrons release energy in fixed amounts
- In their ground state, atoms have their electrons in their lowest
possible energy levels
Topics Comprehensive 2024 Exam Quiz
Study Guide
Atoms - Answer>>Made up of 3 subatomic particles - electrons,
neutrons and protons
Electrons - Answer>>- Subatomic particle
- Charge of -1
- Arranged in orbitals
- Relative mass of 0.0005 - negligible
Nucleus - Answer>>- Where most of the mass of the atom is
contained
- Made up of protons and neutrons
- Diameter is much smaller than that of whole atom
Neutrons - Answer>>- Subatomic particle
- No charge
- Relative mass of 1
- Contained in nucleus
- Dictates the isotope of an element that an atom is; not all atoms
of the same element have the same number of neutrons
Protons - Answer>>- Subatomic particle
- Charge of +1
- Relative mass of 1
- Contained in nucleus
- Dictates the type of element that an atom is; all atoms of the
same element have the same number of protons
Ions - Answer>>- Ions are charged atoms; positive ions have
more protons than electrons, and vice versa for negative ions
,- Ions have different numbers of electrons to their parent
elements'
- e.g. Li⁺ has only 2 electrons, whereas Li has 3
- e.g. F has 9 electrons, F⁻ has 10
Isotopes - Answer>>- Isotopes of an element are atoms with the
same number of protons but a different number of neutrons.
- E.g. ³⁵Cl has 18 neutrons and ³⁷Cl has 20
- Number and arrangement of electrons dictate the chemical
properties of an element, so all isotopes of an element have the
same chemical properties
- However isotopes of the same element can have different
physical properties such as density and diffusion rates
Relative atomic mass - Answer>>The relative atomic mass is
the weighted mean mass of an atom of an element compared to
1/12th of the mass of an atom of carbon-12
Can be worked out from Isotopic Abundances - Multiply the
isotopic mass of each isotope by its % abundance, add them up
then divide the total by 100
Relative isotopic mass - Answer>>The mass of an atom of an
isotope of an element compared with 1/12th if the mass of an
atom of carbon-12
Relative molecular/formula mass - Answer>>The average mass
of a molecule compared to the mass of an atom of carbon-12
Mass Spectrometry - Answer>>Can be used to work out the
relative atomic mass. Particles measured with a mass
spectrometer must be charged, so they are often bombarded with
electrons in order to remove one, giving a charge of +1
,1. Multiply each relative isotopic mass by its relative isotopic
abundance, and add up the results
2. Divide by the sum of the isotopic abundances
Calculating Isotopic Masses from Relative atomic mass -
Answer>>Need: Relative mass of element and all but one of the
abundances and isotopic masses of its isotopes
1. Find abundance of last isotope; percentage abundances so do
100-(sum of known% abundances)
2. Put into equation for finding the relative atomic mass and
rearrange for the unknown value
Predicting mass spectra for diatomic molecules (E.g. Cl₂) -
Answer>>1. Express each % as a decimal (e.g. 75%→0.75 and
25%→0.25)
2. Make a table showing all the different Cl₂ molecules. For each,
multiply the abundances of each isotope to get the relative
abundance of each molecule.
3. Look for any values in the table that are the same and add up
their abundances
4. Divide all the relative abundances by the smallest relative
abundance to get the smallest whole number ratio. And by
working out the relative molecular mass of each molecule, you
can predict the mass spectra
5. Plot the mass spectra with the relative abundances you worked
out on the y-axis and the relative molecular masses (m/z) on the
x-axis
Identifying compounds using mass spectrometry - Answer>>1.
Molecules in a sample are bombarded with electrons to remove
an electron and form a molecular ion, M⁺
2. The molecular mass is shown by the molecular ion peak - the
peak with the highest m/z value, not including any M+1 peaks
caused by presence of carbon-13
, Electron Shells - Answer>>- Made up of subshells and orbitals
- Electrons move around the nucleus in quantum shells (aka
energy levels)
- Shells further from the nucleus have a greater energy level than
those closer to the nucleus
- Shells contain different types of subshell, each of which have
different numbers of orbitals which can each hold 2 electrons
Subshells - Answer>>This table shows the subshells and how
many electrons can be contained in each.
Orbitals - Answer>>- Orbitals within the same subshell have the
same energy
- s-orbitals are spherical
- p-orbitals are dumbbell-shaped. There are 3 p-orbitals and they
are at right angles to each other
Electronic configuration - Answer>>- Electrons fill up the lowest
energy subshells first
- Electrons fill orbitals singly before they start pairing up
- Exceptions: Chromium and Copper - donate a 4s electron to the
3d subshell because they are more stable with a full or half-full d-
subshell
Periodic table electron configuration blocks - Answer>>- s-block
elements have an outer shell electronic configuration of s¹ or s²
- p-block elements have an outer shell electronic configuration of
s²p¹ to s²p⁶
Atomic emission spectra - electron excitement - Answer>>-
Electrons release energy in fixed amounts
- In their ground state, atoms have their electrons in their lowest
possible energy levels
