AQA GCSE Chemistry - Paper 1
Aluminium Oxide - Anode Half Equation - ANS-2O(two minus) --> O2 + 4e(minus)
\Aluminium Oxide - Cathode Half Equation - ANS-Al(three plus) + 3e(minus) --> Al
\Anode - ANS-Positive electrode
Negative ions move towards it
Electrons are lost
Oxidation happens
\Anode - If there are halogen ions (halide ions)... - ANS-...They will be released from the
anode
\Anode - If there are no halogen ions (halide ions)... - ANS-...Oxygen will be produced
\Are metal carbonates bases or acids? - ANS-Bases
\Are metal oxides and hydroxides bases or acids? - ANS-Bases
\Are the noble gases flammable? - ANS-No - they're non-flammable
\Benefits of Nanoparticles - ANS-1) Used in sun creams - shown to be better than the
materials in traditional sun creams at protecting skin from harmful UV rays
2) Give better skin coverage than traditional sun creams
\Boiling - ANS-When a liquid is heated, the particles will gain even more energy, making
them move faster - weakens and breaks the bonds holding them together
At the boiling point, the particles have enough energy to break their bonds - the liquid
becomes a gas
\Can a molten ionic compound be electrolysed? - ANS-Yes, because the ions can move
freely and conduct electricity
\Can an ionic solid be electrolysed? - ANS-No, because the ions are in fixed positions and
can't move
\Cathode - ANS-Negative electrode
Positive ions move towards it
Electrons are gained
Reduction happens
\Cathode - If the element is less reactive than hydrogen... - ANS-...The element will be
released from the cathode
\Cathode - If the element is more reactive than hydrogen... - ANS-...Hydrogen gas will be
produced
\Change of Mass - Decrease - ANS-If the mass decreases, it's probably because one of the
products is a gas and all the reactants are solids, liquids or aqueous
Before the reaction, all the reactants are contained in the reaction vessel
If the vessel isn't enclosed, then the gas can escape from the reaction vessel as it's formed
It's no longer contained in the reaction vessel, so you can't account for its mass - the total
mass of the stuff inside the reaction vessel decreases
\Change of Mass - Increase - ANS-If the mass increases, it's probably because one of the
reactants is a gas that's found in the air (e.g. oxygen) and all the products are solids, liquids
or aqueous
Before the reaction, the gas is floating around in the air - it's there, but it's not contained in
the reaction vessel, so you can't account for its mass
, When the gas reacts to form part of the product, it becomes contained inside the reaction
vessel - so the total mass of the stuff inside the reaction vessel increases
\Chlorine Half Equation - ANS-2Cl(minus) --> Cl2 + 2e(minus)
\Condensing - ANS-As a gas cools, the particles no longer have enough energy to overcome
the force of attraction between them, causing bonds to form between the particles
At the boiling point, so many bonds have formed between the gas particles that the gas
becomes a liquid
\Describe giant covalent structures - ANS--All the atoms are bonded to each other by strong
covalent bonds
-They have very high melting and boiling points, therefore, lots of energy is required to break
the covalent bonds
-Most of them don't conduct electricity because they don't contain delocalised electrons or
ions
\Describe how an ionic bond forms - ANS-When a metal and a non-metal react together, the
metal loses its one electron on its outer shell to form a positively charged ion. This one
electron is gained by the non-metal to complete its outer shell, forming a negative ion.
\Describe how covalent bonds form - ANS-When two non-metals bond together, they share
electrons to make covalent bonds. The positively charged nuclei of the bonded atoms are
attracted to the shared pair of electrons by electrostatic forces - this makes covalent bonds
very strong.
\Describe the properties of diamond - ANS--Very hard because of its structure
-Very high melting point because it takes a lot of energy to break the bonds
-No delocalised electrons, therefore it cannot conduct electricity
\Describe the structure of a crystal of sodium chloride - ANS-It's a giant ionic lattice. The
positive sodium and negative chlorine ions form a closely packed regular arrangement and
there are very strong electrostatic forces of attraction between the oppositely charged ions.
\Describe the structure of a polymer - ANS-Polymers are long chains of repeating units
joined together to make a long molecule. Between the atoms are strong covalent bonds.
\Describe the structure of diamond - ANS-Each carbon atom forms four strong covalent
bonds in a very rigid giant covalent structure.
\Describe the structure of graphite - ANS-Each carbon atom forms three covalent bonds to
create layers of hexagons. Each carbon atom also has one delocalised electron.
\Do nanoparticles have a high or low surface area to volume ratio? - ANS-Very high surface
area to volume ratio - the surface area is very large compared to the volume, therefore, they
make good catalysts
\Effects of Nanoparticles on Health - ANS-1) The way they affect the body isn't fully
understood
2) Some people are worried that products containing them have been made available before
the effects on human health have been investigated properly
3) We don't know what the long-term impacts on health will be
4) Many people believe that products containing nanoparticles should be clearly labelled
\Empirical Formula - ANS-1) Divide the mass of each substance by its relative formula mass
to find the number of moles
2) Divide the number of moles of each substance by the smallest number of moles in the
reaction
3) If any of the numbers aren't whole numbers, multiply all the numbers by the same amount
so that they all become whole numbers
Aluminium Oxide - Anode Half Equation - ANS-2O(two minus) --> O2 + 4e(minus)
\Aluminium Oxide - Cathode Half Equation - ANS-Al(three plus) + 3e(minus) --> Al
\Anode - ANS-Positive electrode
Negative ions move towards it
Electrons are lost
Oxidation happens
\Anode - If there are halogen ions (halide ions)... - ANS-...They will be released from the
anode
\Anode - If there are no halogen ions (halide ions)... - ANS-...Oxygen will be produced
\Are metal carbonates bases or acids? - ANS-Bases
\Are metal oxides and hydroxides bases or acids? - ANS-Bases
\Are the noble gases flammable? - ANS-No - they're non-flammable
\Benefits of Nanoparticles - ANS-1) Used in sun creams - shown to be better than the
materials in traditional sun creams at protecting skin from harmful UV rays
2) Give better skin coverage than traditional sun creams
\Boiling - ANS-When a liquid is heated, the particles will gain even more energy, making
them move faster - weakens and breaks the bonds holding them together
At the boiling point, the particles have enough energy to break their bonds - the liquid
becomes a gas
\Can a molten ionic compound be electrolysed? - ANS-Yes, because the ions can move
freely and conduct electricity
\Can an ionic solid be electrolysed? - ANS-No, because the ions are in fixed positions and
can't move
\Cathode - ANS-Negative electrode
Positive ions move towards it
Electrons are gained
Reduction happens
\Cathode - If the element is less reactive than hydrogen... - ANS-...The element will be
released from the cathode
\Cathode - If the element is more reactive than hydrogen... - ANS-...Hydrogen gas will be
produced
\Change of Mass - Decrease - ANS-If the mass decreases, it's probably because one of the
products is a gas and all the reactants are solids, liquids or aqueous
Before the reaction, all the reactants are contained in the reaction vessel
If the vessel isn't enclosed, then the gas can escape from the reaction vessel as it's formed
It's no longer contained in the reaction vessel, so you can't account for its mass - the total
mass of the stuff inside the reaction vessel decreases
\Change of Mass - Increase - ANS-If the mass increases, it's probably because one of the
reactants is a gas that's found in the air (e.g. oxygen) and all the products are solids, liquids
or aqueous
Before the reaction, the gas is floating around in the air - it's there, but it's not contained in
the reaction vessel, so you can't account for its mass
, When the gas reacts to form part of the product, it becomes contained inside the reaction
vessel - so the total mass of the stuff inside the reaction vessel increases
\Chlorine Half Equation - ANS-2Cl(minus) --> Cl2 + 2e(minus)
\Condensing - ANS-As a gas cools, the particles no longer have enough energy to overcome
the force of attraction between them, causing bonds to form between the particles
At the boiling point, so many bonds have formed between the gas particles that the gas
becomes a liquid
\Describe giant covalent structures - ANS--All the atoms are bonded to each other by strong
covalent bonds
-They have very high melting and boiling points, therefore, lots of energy is required to break
the covalent bonds
-Most of them don't conduct electricity because they don't contain delocalised electrons or
ions
\Describe how an ionic bond forms - ANS-When a metal and a non-metal react together, the
metal loses its one electron on its outer shell to form a positively charged ion. This one
electron is gained by the non-metal to complete its outer shell, forming a negative ion.
\Describe how covalent bonds form - ANS-When two non-metals bond together, they share
electrons to make covalent bonds. The positively charged nuclei of the bonded atoms are
attracted to the shared pair of electrons by electrostatic forces - this makes covalent bonds
very strong.
\Describe the properties of diamond - ANS--Very hard because of its structure
-Very high melting point because it takes a lot of energy to break the bonds
-No delocalised electrons, therefore it cannot conduct electricity
\Describe the structure of a crystal of sodium chloride - ANS-It's a giant ionic lattice. The
positive sodium and negative chlorine ions form a closely packed regular arrangement and
there are very strong electrostatic forces of attraction between the oppositely charged ions.
\Describe the structure of a polymer - ANS-Polymers are long chains of repeating units
joined together to make a long molecule. Between the atoms are strong covalent bonds.
\Describe the structure of diamond - ANS-Each carbon atom forms four strong covalent
bonds in a very rigid giant covalent structure.
\Describe the structure of graphite - ANS-Each carbon atom forms three covalent bonds to
create layers of hexagons. Each carbon atom also has one delocalised electron.
\Do nanoparticles have a high or low surface area to volume ratio? - ANS-Very high surface
area to volume ratio - the surface area is very large compared to the volume, therefore, they
make good catalysts
\Effects of Nanoparticles on Health - ANS-1) The way they affect the body isn't fully
understood
2) Some people are worried that products containing them have been made available before
the effects on human health have been investigated properly
3) We don't know what the long-term impacts on health will be
4) Many people believe that products containing nanoparticles should be clearly labelled
\Empirical Formula - ANS-1) Divide the mass of each substance by its relative formula mass
to find the number of moles
2) Divide the number of moles of each substance by the smallest number of moles in the
reaction
3) If any of the numbers aren't whole numbers, multiply all the numbers by the same amount
so that they all become whole numbers
