https://filestore.aqa.org.uk/resources/chemistry/specifications/AQA-8462-SP-2016.PDF
https://qualifications.pearson.com/content/dam/pdf/GCSE/Science/2016/teaching-and-learning-
materials/GCSE-9-1-Sciences-core-practical-guide.pdf?_gl=1*wlag66*_ga*MTcxMjk2MjI2My4x
NjcxMzk4MDMz*_ga_K8MHCWK5EH*MTY3MTM5ODAzMi4xLjAuMTY3MTM5ODAzMi4wLjAu
MA..
Atomic Structure (C1):
Scientific models of atom:
● Plum pudding model → Thomson
- a ball of positive charge
- with negative electrons embedded in it
● Nuclear model → Rutherford
- conducted the gold foil experiment
- fired alpha particles at a sheet of thin gold foil
- according to the plum pudding model, the alpha particles should travel thru without
getting deflected
- some deflected, so they found that positive charge was concentrated in the middle
- discovered the nucleus
● Planetary model → Bohr
- suggested that the electrons orbit the nucleus at specific distances from the nucleus
● Chadwick
- figured that protons make up the positive charge
- discovered neutrons, as having a mass but no charge, and are also found in the
nucleus
Atomic structure:
● Atomic radius of an atom = 0.1 nm
● Nanometer = 1 billionth of a metre
● Nucleus = 1/10,000 of an atom
● Nucleus is fixed in place, electrons move around the nucleus in shells
● Atomic number = how many protons there are (therefore how many electrons too)
● atomic mass = no. of protons + neutrons
Relative atomic mass:
● Isotope → is an atom of the same element which has the same no. of protons, but
DIFFERENT no. of neutrons. Therefore it has the same atomic number, but a different
mass number.
● relative atomic mass → the weighted mean mass of an element, taking into account all
of the different isotopes and their relative abundance
● Equation → mass of isotope x abundance / 100
Atoms → all substances are made of atoms. They are the smallest part of an element that can
exist.
Ion → a charged atom (when an atom loses or gains electrons)
,Compounds → contain 2 or more elements chemically combined in fixed proportions. Can only
be separated into elements by chemical reactions.
Separating mixtures:
● Mixture: consists of 2 or more elements or compounds not chemically combined. Can be
separated by physical processes.
● Filtration: used to separate substances that are insoluble in a particular solvent from
those that are soluble in the solvent.
● Filtration process:
- Have the mixture you are filtering in a beaker
- Set up a conical flask or a beaker with a filter funnel and filter paper inside the
funnel.
- Pour the mixture into the filter paper
- The liquid particles are small enough to pass through the filter paper but the solid
particles are too big and are left behind
- The solid left behind is called the residue and the liquid that passed through is
the filtrate
● Crystallisation: separates a soluble solid from a solvent (evaporation)
● Crystallisation (evaporation) process:
- A solution is placed in an evaporating dish and heated with a Bunsen burner
- As the solution is heating, the water in the solution will evaporate into a gas
- As this happens the solid, which were dissolved in the water, are left behind
● Distillation: collecting the solvent from crystallisation instead of letting it evaporate
(condensing at the end)
● Simple distillation process:
- Set up the apparatus with the solution in a round bottom flask which is fitted with
a condenser so any gases produced will travel through the condenser
- Heat the solution w a bunsen burner
- As the liquid heats up, it evaporates and the vapour condenses and turns back
into a liquid
- Liquid droplets are collected in a beaker at the end
- Leaving the solid in the round bottom flask
● fractional distillation: separating mixtures of miscible liquids that have different boiling
points.
● Paper chromatography: a technique used to separate and identify substance from
mixtures in solution
,Periodic Table (C2):
Development of the periodic table:
● Most recent periodic tables will show about 110 different elements
● Now, we order the elements according to their atomic number
● The early periodic tables ordered the elements according to their atomic weights
● “Law of Triads” → early scientists tried to group elements in triads, according to their
reactivity - this didn't work
● Newlands invented the “Law of Octaves” as he noticed that the properties of elements
repeated every 8 elements. - was still inconsistent
● Mendelev (God father of the Periodic Table) → he left gaps for elements that were not
discovered yet, but still ordered the table in order of the atomic weight.
● Using his table, you could see groups of elements had the same reactions. So you could
predict the properties of the elements we had not found yet. Then we filled the gaps he
left.
● Elements in the same group, have the same no. of electrons in the outer shell → similar
chemical properties
● Rows are called periods, members of the same period will have the same number of
electron shells.
● Metals on the left, non-metals are on the right
Group 0 - The Noble Gases
● Have full outer shells → are stable
● Very unreactive, or inert
● Don't form molecules
● Properties: colourless gases, low b.p, density and b.p increases down the group
Group 1 - Alkali metals
● All have one electron in their outer shell - must lose this electron to become stable
● This means they become +1 ions
● Properties: low densities (float), soft (can be cut with a knife), shiny only when cut, very
reactive, reactivity increases down the group - because the electron is further away from
the nucleus (positively charged), so the force of attraction is weaker
● React with oxygen - metal + oxygen → metal oxide
● They burn vigorously forming white smoke
● Group 1 oxides dissolve in water to form metal hydroxides
● React with chlorine - metal + chlorine → metal chloride
● Very vigorous, produces a salt, colourless solutions
● React with water - metal + water → metal hydroxide + hydrogen
● Very vigorous, fizzing/bubbles, floats and moves, metal dissolves, solution is alkaline
● Group 1 metals are usually stored in .oil, to prevent them from reacting with the air and
water
, Group 7 - The Halogens
● All non metals
● All have 7 electrons in their outer shell
● Exist as diatomic molecules
● Low m.p and b.p
● Usually gases or liquids
● As you go down the group, the mp and bp increase
● At room temperature: F2 - gas, Cl2 - gas, Br2 - liquid, I2 - solid, At2 - solid
● Quite reactive
● React easily with metals to form halide ions (white salts, dissolve to become colourless),
usually resulting in the halogen to become a -1 charge
● As you go down the group, they become LESS reactive, because all elements have 7
electrons in their outer shell, so when they react they gain 1 electron. The nucleus has a
positive charge, and it is what attracts the electron in, so the further the nucleus is from
the outer shell, the weaker the force of attraction, so it's harder to gain an electron
● A more reactive halogen can displace a less reactive halogen from a solution of its salt
Transition elements
● In comparison to group 1 elements, transition metals have: higher melting points, are
stronger and harder, much less reactive
● They form + ions with a variety of charges (oxidation states)
● They also form coloured compounds
● Useful as catalysts
Structure and Bonding (C3):
States of matter:
●
● Solids
○ Packed together in a regular pattern
○ Fixed shape
○ Vibrate in fixed positions
○ Has the least kinetic energy
● Liquids
○ Particles slip and slide over each other
○ The particle take the shape of their container
○ More kinetic energy than solids but less than gases
● Gases
https://qualifications.pearson.com/content/dam/pdf/GCSE/Science/2016/teaching-and-learning-
materials/GCSE-9-1-Sciences-core-practical-guide.pdf?_gl=1*wlag66*_ga*MTcxMjk2MjI2My4x
NjcxMzk4MDMz*_ga_K8MHCWK5EH*MTY3MTM5ODAzMi4xLjAuMTY3MTM5ODAzMi4wLjAu
MA..
Atomic Structure (C1):
Scientific models of atom:
● Plum pudding model → Thomson
- a ball of positive charge
- with negative electrons embedded in it
● Nuclear model → Rutherford
- conducted the gold foil experiment
- fired alpha particles at a sheet of thin gold foil
- according to the plum pudding model, the alpha particles should travel thru without
getting deflected
- some deflected, so they found that positive charge was concentrated in the middle
- discovered the nucleus
● Planetary model → Bohr
- suggested that the electrons orbit the nucleus at specific distances from the nucleus
● Chadwick
- figured that protons make up the positive charge
- discovered neutrons, as having a mass but no charge, and are also found in the
nucleus
Atomic structure:
● Atomic radius of an atom = 0.1 nm
● Nanometer = 1 billionth of a metre
● Nucleus = 1/10,000 of an atom
● Nucleus is fixed in place, electrons move around the nucleus in shells
● Atomic number = how many protons there are (therefore how many electrons too)
● atomic mass = no. of protons + neutrons
Relative atomic mass:
● Isotope → is an atom of the same element which has the same no. of protons, but
DIFFERENT no. of neutrons. Therefore it has the same atomic number, but a different
mass number.
● relative atomic mass → the weighted mean mass of an element, taking into account all
of the different isotopes and their relative abundance
● Equation → mass of isotope x abundance / 100
Atoms → all substances are made of atoms. They are the smallest part of an element that can
exist.
Ion → a charged atom (when an atom loses or gains electrons)
,Compounds → contain 2 or more elements chemically combined in fixed proportions. Can only
be separated into elements by chemical reactions.
Separating mixtures:
● Mixture: consists of 2 or more elements or compounds not chemically combined. Can be
separated by physical processes.
● Filtration: used to separate substances that are insoluble in a particular solvent from
those that are soluble in the solvent.
● Filtration process:
- Have the mixture you are filtering in a beaker
- Set up a conical flask or a beaker with a filter funnel and filter paper inside the
funnel.
- Pour the mixture into the filter paper
- The liquid particles are small enough to pass through the filter paper but the solid
particles are too big and are left behind
- The solid left behind is called the residue and the liquid that passed through is
the filtrate
● Crystallisation: separates a soluble solid from a solvent (evaporation)
● Crystallisation (evaporation) process:
- A solution is placed in an evaporating dish and heated with a Bunsen burner
- As the solution is heating, the water in the solution will evaporate into a gas
- As this happens the solid, which were dissolved in the water, are left behind
● Distillation: collecting the solvent from crystallisation instead of letting it evaporate
(condensing at the end)
● Simple distillation process:
- Set up the apparatus with the solution in a round bottom flask which is fitted with
a condenser so any gases produced will travel through the condenser
- Heat the solution w a bunsen burner
- As the liquid heats up, it evaporates and the vapour condenses and turns back
into a liquid
- Liquid droplets are collected in a beaker at the end
- Leaving the solid in the round bottom flask
● fractional distillation: separating mixtures of miscible liquids that have different boiling
points.
● Paper chromatography: a technique used to separate and identify substance from
mixtures in solution
,Periodic Table (C2):
Development of the periodic table:
● Most recent periodic tables will show about 110 different elements
● Now, we order the elements according to their atomic number
● The early periodic tables ordered the elements according to their atomic weights
● “Law of Triads” → early scientists tried to group elements in triads, according to their
reactivity - this didn't work
● Newlands invented the “Law of Octaves” as he noticed that the properties of elements
repeated every 8 elements. - was still inconsistent
● Mendelev (God father of the Periodic Table) → he left gaps for elements that were not
discovered yet, but still ordered the table in order of the atomic weight.
● Using his table, you could see groups of elements had the same reactions. So you could
predict the properties of the elements we had not found yet. Then we filled the gaps he
left.
● Elements in the same group, have the same no. of electrons in the outer shell → similar
chemical properties
● Rows are called periods, members of the same period will have the same number of
electron shells.
● Metals on the left, non-metals are on the right
Group 0 - The Noble Gases
● Have full outer shells → are stable
● Very unreactive, or inert
● Don't form molecules
● Properties: colourless gases, low b.p, density and b.p increases down the group
Group 1 - Alkali metals
● All have one electron in their outer shell - must lose this electron to become stable
● This means they become +1 ions
● Properties: low densities (float), soft (can be cut with a knife), shiny only when cut, very
reactive, reactivity increases down the group - because the electron is further away from
the nucleus (positively charged), so the force of attraction is weaker
● React with oxygen - metal + oxygen → metal oxide
● They burn vigorously forming white smoke
● Group 1 oxides dissolve in water to form metal hydroxides
● React with chlorine - metal + chlorine → metal chloride
● Very vigorous, produces a salt, colourless solutions
● React with water - metal + water → metal hydroxide + hydrogen
● Very vigorous, fizzing/bubbles, floats and moves, metal dissolves, solution is alkaline
● Group 1 metals are usually stored in .oil, to prevent them from reacting with the air and
water
, Group 7 - The Halogens
● All non metals
● All have 7 electrons in their outer shell
● Exist as diatomic molecules
● Low m.p and b.p
● Usually gases or liquids
● As you go down the group, the mp and bp increase
● At room temperature: F2 - gas, Cl2 - gas, Br2 - liquid, I2 - solid, At2 - solid
● Quite reactive
● React easily with metals to form halide ions (white salts, dissolve to become colourless),
usually resulting in the halogen to become a -1 charge
● As you go down the group, they become LESS reactive, because all elements have 7
electrons in their outer shell, so when they react they gain 1 electron. The nucleus has a
positive charge, and it is what attracts the electron in, so the further the nucleus is from
the outer shell, the weaker the force of attraction, so it's harder to gain an electron
● A more reactive halogen can displace a less reactive halogen from a solution of its salt
Transition elements
● In comparison to group 1 elements, transition metals have: higher melting points, are
stronger and harder, much less reactive
● They form + ions with a variety of charges (oxidation states)
● They also form coloured compounds
● Useful as catalysts
Structure and Bonding (C3):
States of matter:
●
● Solids
○ Packed together in a regular pattern
○ Fixed shape
○ Vibrate in fixed positions
○ Has the least kinetic energy
● Liquids
○ Particles slip and slide over each other
○ The particle take the shape of their container
○ More kinetic energy than solids but less than gases
● Gases
