1
Q
Practical for investigating the solubility of a solid in water at different temperatures
A
- pour 200cm^3 of deionised water into a 250cm^3 beaker
- use a water bath to heat the beaker of water to a desired temperature. Keep thermometer in the beaker to ensure temperature stays constant
- add known masses of the solid bit by bit until the solid stops dissolving and remains as solid in the solution
- record the mass of the solid that was soluble
Repeat steps 1-4 for different temperatures
2
Q
Finding the formula of a metal oxide experimentally
A
- weigh crucible lid and crucible
- place the magnesium ribbon in the crucible, replace lid and reweigh
- calculate mass of magnesium
- heat crucible with lid on until the magnesium burns
- lift lid from time to time to allow oxygen in
- Stop heating when there is no more sign of reaction
- allow to cool and reweigh
- repeat the heating, cooling and re weighing until two consecutive masses are the same
- calculate mass of magnesium oxide formed
3
Q
Calculating experimental masses using experimental data and chemical equations
A
- calculate amount of x in moles
- deduce the amount of moles in y produced from amount of moles in x by using the ratio
- calculate the mass of the amount of moles in y
4
Q
Test for displacement, dissolving and neutralisation reactions
A
- Ass 50cm3 of copper (II) sulfate into a polystyrene cup
- The initial temp of the copper sulfate solution is measured and recorded
- Magnesium is added and the maximum temperature is measured and recorded
- The temperature rise is then calculated
5
Q
Test for combustion reactions
A
- Initial mass of ethanol and spirit burner is measured and recorded
- 100cm3 of water is transferred into a copper container and the initial temp is measured and recorded
- The burner is places under the copper container and then lit
- The water is stirred constantly until temperature rises by 30C
- The flame is extinguished and the maximum temperature of the water is measured and recorded
- The burner and the remaining ethanol is reweighed
6
Q
Marble chips and hydrochloric acid
A
- Marble chips of different sizes are reacted with hydrochloric acid to produce carbon dioxide
- At different points in the reaction mass loss is recorded and then plotted on a graph to represent rate of reaction
- cotton wool is placed in top of beaker to prevent acid from spraying out but to allow carbon dioxide to escape
7
Q
Prepare a sample of an ester such as ethyl ethanoate
A
- Heat a mixture of ethanoic acid and ethanol
- add a few drops of sulfuric acid for the reaction to work
- in this case, the sulphuric acid is the catalyst
- a liquid called ethyl ethanoate will be formed
- this reaction is reversible
