Year 7 to 8
Name the state change from gas to solid
Identify the three subatomic particles
Protons, electrons, neutrons
How many water molecules in 1 mol of water.
6.02 x 10^23 water molecules
Name 4 different non-renewable fuels in SD (no random specific one > general ones we learnt)
petrol, diesel, natural gas, coal, kerosene,
The concentration of products decrease.
Identify what reaction is favoured
Forwards
Name the three main types of arrangements for particles
Monoatomic, molecular, lattice
Describe the overall trend in reactivity down a period.
Increases due to increased atomic radii
Describe the metallic bonding model
A lattice or regular arrangement of metallic cations surrounded by delocalised electrons forming strong electrostatic attractions between each other.
Describe the purpose of calorimetry
To determine the energy released or absorbed by a chemical reaction
State all the factors that affect ROR
temperature, surface area, concentration, gas pressures, presence of a catalyst, activation energy
Identify at least 5 different seperation techniques
Distillation, filtration, decantation, chromatography, crystallisation, evaporation, distillation
Explain why chemical equations must be balanced
Due to the conservation of mass, atoms/mass cannot be created nor destroyed
Describe the chemical structure of a monomer for a polymer that is heat resistant
Unbranched, polar functional groups, regular arrangement, cross-linked
Identify 4 differences or similarities between fuel cells and primary galvanic cells
Various answers
2A <> B
Explain using LCP, how the yield is affected when the system is diluted
A dilution would decrease all concentrations.
To partially oppose this decrease in concnetrations, the system favours the backwards reaction to as there are more particles on the LHS.
This would decrease yield
Explain the difference between a chemical and physical change
A chemical change involves the rearrangement of intramolecular forces and a new substance being created, whilst a physical change does not.
Name 3 different reaction types (redox doesn't count they don't learn it)
Synthesis, decomposition, displacement
Acid-base, neutralisation, precipitation.
Identify what data is obtained from gravimetric analysis and explain briefly how this is done.
Identify the concentration/mass of an ion.
Use a solution to precipitate out the ion. Measure the mass of the precipitate and use stoichiometry to backtrack.
1. mass/mole of metal electrolysed is directly proportional to total electric charge passed
2.amount of metal plated is inversely proportional to charge of ion
The products of discharge must be in contact with the electrode.
A minimum voltage of the Ecell or more must be applied to cause the non-spontaneous reaciton to occur
Explain why liquids take the shape of their container whilst solids have a fixed shape with reference to the particle model.
Liquids have less forces of attraction thus their particles move freely and fill the container they are in. Solids have fixed shapes as they have more forces of attraction and are unable to move freely taking fixed positions.
Explain why non-metallic character increases closer as you go further right of a period and up a group.
Atomic radii gets smaller due to the decreased amount of shells. This increases the electrostatic attraction and increases the chance of gaining an electron.
List out the five postulates of the kinetic theory of gasses (ideal gas)
1. Gasses are small far apart and most of the volume is empty space
2. Gas particles are on constant random motion in straight lines.
3. All collisions are elastic and kinetic energy is conserved
4. No intermolecular forces are present
5. Average KE is directly proportional to temp.
Explain why exothermic reactions release energy with reference to bond breaking and formation
The amount of energy requried to break bonds in reactants in a chemical reaction is less than the amount of energy released during bond formation into products
Explain what is meant by the conflict of rate and temperature and how it can be alleviated
For exothermic reactions the rate of reaction is inversely proportional to the extent of reaction or yield as with higher temperatures, there is a lower K and vice versa.
Catalyst use allows for lower temperatures to be used to maximise K but not significantly affect the ROR due to reduction in Ea