CHEMISTRY
Aqa chemistry paper 1 Higher Exam
2025
Filtration - -It removes large, insoluble particles from a liquid.
e.g. sand from water
Evaporation/crystallization - -leaves behind crystals of a dissolved substance if heated
gently
Distillation - -condensing and evaporating a solvent and then collecting it
Fractional distillation - -separates liquids due to their boiling points
Chromatography - -causes a substance for rise up paper due to capillary action. Lighter
particles move further up .
Solid - -vibrate about fixed positions
regular lattice arrangement
cannot be compressed
Liquid - -no regular arrangement and can move past each other
cannot be compressed
Gas - -particles are far apart
move randomly at fast speeds
can be compressed
What is needed to overcome the electrostatic forces of attraction between the particles
to melt/evaporate? - -heat energy
What model of the atom did JJ Thomson design - -Plum pudding model.
Sphere of positive mass and negative particles randomly inside.
Ernest Rutherford - -discovered that the nucleus was small and postively charged by
finding most alpha particles went straight through a gold leaf and few were deflected
back.
Neil’s Bohr - -dedecued that elections exist in shells.
James chadwick - -determinded that the nucleus must contain neutrons as well as
protons
CHEMISTRY
, CHEMISTRY
What did mendeleev do - -left gaps in his table for unknown elements and made
predictions about their properties
How was the periodic table ordered before mendeleev - -ordered by atomic weight due
to having similar properties
What are group 1 metals and their properties - -alkali metals
They lose outer electron to form positive ions
They are more reactive down the group as the electron is further away from the nucleus
and the force of attraction is lost
What are group 7 called and their properties - -halogens
form -1 ions to gain a full outer shell
less reactive as you go down the group and the boiling point increases
Nobel gases - -group 0 are very unreactive as they have an empty outer shell
What is metallic bonding? - -It involves a lattice of ions surrounded by a sea of
delocalized electrons.
Why are metals good conductors of electricity and heat ? - -Metals are good conductors
of electricity because of the free movement of delocalized electrons.
ionic bonding - -between metals and non metals
metal atoms donate electrons to non metals to form ions
What is the structure of ionic compounds? - -Ions are arranged in a lattice of repeating
positive and negative ions to form a crystal.
Why do ionic substances have high melting and boiling points? - -Due to the strong
ionic bonds present in the lattice structure.
In what states can ionic compounds conduct electricity? - -When molten or in solution,
as the ions are free to move and carry a charge.
What are positive ions called? - -Cations.
What are negative ions called? - -Anions.
What is another name for ionic compounds? - -Salts.
What are molecules - -two or more atoms bonded together
What are compounds - -substances in which atoms of two
or more elements are chemically combined
CHEMISTRY
Aqa chemistry paper 1 Higher Exam
2025
Filtration - -It removes large, insoluble particles from a liquid.
e.g. sand from water
Evaporation/crystallization - -leaves behind crystals of a dissolved substance if heated
gently
Distillation - -condensing and evaporating a solvent and then collecting it
Fractional distillation - -separates liquids due to their boiling points
Chromatography - -causes a substance for rise up paper due to capillary action. Lighter
particles move further up .
Solid - -vibrate about fixed positions
regular lattice arrangement
cannot be compressed
Liquid - -no regular arrangement and can move past each other
cannot be compressed
Gas - -particles are far apart
move randomly at fast speeds
can be compressed
What is needed to overcome the electrostatic forces of attraction between the particles
to melt/evaporate? - -heat energy
What model of the atom did JJ Thomson design - -Plum pudding model.
Sphere of positive mass and negative particles randomly inside.
Ernest Rutherford - -discovered that the nucleus was small and postively charged by
finding most alpha particles went straight through a gold leaf and few were deflected
back.
Neil’s Bohr - -dedecued that elections exist in shells.
James chadwick - -determinded that the nucleus must contain neutrons as well as
protons
CHEMISTRY
, CHEMISTRY
What did mendeleev do - -left gaps in his table for unknown elements and made
predictions about their properties
How was the periodic table ordered before mendeleev - -ordered by atomic weight due
to having similar properties
What are group 1 metals and their properties - -alkali metals
They lose outer electron to form positive ions
They are more reactive down the group as the electron is further away from the nucleus
and the force of attraction is lost
What are group 7 called and their properties - -halogens
form -1 ions to gain a full outer shell
less reactive as you go down the group and the boiling point increases
Nobel gases - -group 0 are very unreactive as they have an empty outer shell
What is metallic bonding? - -It involves a lattice of ions surrounded by a sea of
delocalized electrons.
Why are metals good conductors of electricity and heat ? - -Metals are good conductors
of electricity because of the free movement of delocalized electrons.
ionic bonding - -between metals and non metals
metal atoms donate electrons to non metals to form ions
What is the structure of ionic compounds? - -Ions are arranged in a lattice of repeating
positive and negative ions to form a crystal.
Why do ionic substances have high melting and boiling points? - -Due to the strong
ionic bonds present in the lattice structure.
In what states can ionic compounds conduct electricity? - -When molten or in solution,
as the ions are free to move and carry a charge.
What are positive ions called? - -Cations.
What are negative ions called? - -Anions.
What is another name for ionic compounds? - -Salts.
What are molecules - -two or more atoms bonded together
What are compounds - -substances in which atoms of two
or more elements are chemically combined
CHEMISTRY
