Required practicals

• How to make a standard solution

  1. Measure the mass of solid required using a balance

  2. Transfer the solid into a volumetric flask and rinse with distilled water to ensure no solid is lost

  3. Add a volume of distilled water to dissolve the solid, swirl to mix

  4. Add more distilled water up to the line on the volumetric flask

  5. Invert the flask multiple times to mix
• How to carry out a titration

  1. Use a pipette to place one reactant into a conical flask

  2. Fill a burette with the other reactant

  3. Record the initial burette volume

  4. Add a few drops of indicator to the conical flask

  5. Open the burette tap to allow the reactant to flow through the flask, swirling to mix

  6. Close the tap once the colour changes, record the final burette volume

  7. Repeat until a concordant result is obtained, then calculate the mean
• Measuring enthalpy change


  1. Weigh out 2g of zinc

  2. Pipette 25cm³ of 0.5 moldm³ copper sulphate solution into a polystyrene cup in a beaker

  3. Place a lid on the cup, put under a tripod and place a thermometer in the hole

  4. Stir and record the temperature every minute

  5. At 4 minutes, add the zinc

  6. Stir and record the temperature every minute for 15 minutes

  7. Plot a graph of temperature vs time and extrapolate to 4 minutes to find the maximum temperature rise

  8. Calculate the enthalpy change
• Measuring the rate of reaction (initial rate method)

  1. Fill a 50cm³ burette with potassium iodide

  2. Transfer 10cm³ of H₂O₂ from the burette to a 100cm³ beaker

  3. Use a 50cm³ measuring cylinder to add 25cm³ of H₂SO₄ to a 250cm³ beaker

  4. Use a 25cm³ beaker to add 25cm³ deionised water to the 250cm³ beaker

  5. Use a pipette to add 1cm³ of starch

  6. Add 5cm³ of KI to the 250cm³ beaker

  7. Use the burette to add 5cm³ of sodium thiosulfate to the mixture in the 250cm³ beaker

  8. Stir the mixture

  9. Add the H₂O₂ from the 100cm³ beaker to the 250cm³ beaker and start the timer

  10. Stop the timer when the mixture turns blue-black and record the time

  11. Repeat the experiment 4 times with different concentrations of potassium iodide

  12. Plot a graph of initial rate (y) vs concentration (x) to determine the order
• Measuring the rate of reaction (continuous monitoring method)

  1. Measure 5cm³ of 20 vol H₂O₂ into a conical flask from a burette

  2. Add 95cm³ of water using a measuring cylinder

  3. Weigh out 0.25g of manganese(IV) oxide catalyst in a weighing boat

  4. Add the manganese(IV) oxide into the conical flask, insert the flask and start the stopwatch

  5. Record the volume of gas every 15 seconds for 3 minutes or until 50cm³ of oxygen has been collected

  6. Plot a graph of concentration vs time and find the gradient at 3 points to determine the rate

  7. Plot a graph of rate vs concentration to find the order of the reaction with respect to the concentration of H₂O₂
• Measuring EMF of an electrochemical cell

  1. File the outer layer of a metal to remove the oxide layer and connect it to the positive voltmeter terminal

  2. Cut a piece of filter paper, saturate it with KNO₃ solution and place it on top of the metal

  3. Connect the voltmeter to another piece of metal and hold it against the paper, recording the value

  4. Repeat with different metals and record the results
• Calibrating a pH probe

  1. Rinse the pH probe thoroughly with deionised water and shake to remove excess

  2. Place the probe in a standard pH 7 solution and record the reading

  3. Repeat using standard pH 4 and 9.2 buffer solutions, recording the readings

  4. Plot a graph of recorded pH (x-axis) against the pH of the buffer (y-axis) and use the graph to adjust pH values
• Measuring pH of an acid-alkali mixture

  1. Rinse a burette with 0.1 moldm³ ethanoic acid and fill it, labelling the burette

  2. Transfer exactly 20cm³ of the ethanoic acid to a 100cm³ clean beaker from the burette

  3. Rinse a second burette with 0.1 moldm³ NaOH and fill it, labelling it

  4. Rinse the pH probe with deionised water and clamp it so the bulb is fully in the ethanoic acid

  5. Use a rod to stir the solution and record the pH

  6. Add 2cm³ of NaOH solution at a time, stir and record the pH and volume of NaOH added

  7. Near the end, add 0.2cm³ each time, stir and record

  8. Keep adding 2cm³ of NaOH until it is in excess, stir and record
• Purifying an organic solid

  1. Dissolve the solid in a pure solvent using the minimum volume

  2. Filter the solution

  3. Cool and crystallise the product

  4. Filter the crystals under reduced pressure

  5. Wash the crystals with cold solvent/water and dry
• Purifying an organic liquid

  1. Put the impure distillate product into a separating funnel

  2. Wash the product with a sodium hydrogencarbonate solution, shake and release the pressure from CO₂

  3. Allow the layers to separate, then run off and discard the aqueous layer

  4. Add 3 spatulas of anhydrous sodium sulphate to the organic layer to absorb any water

  5. Decant the organic liquid into a distillation flask carefully

  6. Distill to collect the pure product
• Identifying transition metals


  1. Add sodium hydroxide to 10 drops of the solution in a test tube, shake gently until in excess, record observations

  2. Half fill a 250cm³ beaker with boiled water, allow 4 test tubes from the first test to stand in the beaker for 10 minutes, record observations

  3. Add 10 drops of sodium carbonate to 10 drops of the solution in a test tube, shake gently, record observations

  4. Add 10 drops of silver nitrate to 10 drops of the solution in a test tube, shake and stand for 10 minutes, record observations
• Iron - brown precipitate
• Copper - blue precipitate
• Copper - white precipitate