Paper 1 Required Practicals Flashcards
What is the practical of the preparation of a pure, dry sample of a soluble salt from an insoluble oxide or carbonate?
❶ add powdered insoluble reactant to acid in a beaker, one spatula at a time and stir to mix.
❷ continue adding powder until it is in excess/some unreacted powder is left over.
❸ filter the mixture in the beaker to remove the excess powder.
❹ collect the filtrate.
❺ pour the filtrate into an evaporating basin.
❻ place the evaporating basin on a water bath and heat until about half the water from the solution has been removed by evaporation.
❼ stop heating when small crystals start to appear around the edge of the evaporating basin.
❽ pour the remaining solution into a watch glass and leave in a warm, dry place for crystallisation to occur.
❾ if necessary, dry the crystals by dabbing gently with filter paper.
What is the practical to determine the reacting volumes of solutions of a strong acid and a strong alkali by titration?
❶ use the pipette and pipette filler to add 25 cm3 of alkali to a clean conical flask.
❷ add a few drops of indicator and put the conical flask on a white tile.
❸ fill the burette with acid and note the starting volume.
❹ slowly add the acid from the burette to the alkali in the conical flask and swirl to mix.
❺ stop adding the acid when the end point is reached which is when the indicator first permanently changes colour and note the final volume reading.
❻ repeat steps 1 to 5 until you get concordant titres. [more accurate results are obtained if acid is added drop by drop near to the end-point]
What is the practical to investigate the variables that affect temperature changes in two reacting solutions such as acid and alkali?
❶ place the polystyrene cup inside the glass beaker to make it more stable.
❷ measure an appropriate volume of each liquid such as 25cm³.
❸ place one of the liquids in a polystyrene cup.
❹ record the temperature of the solution.
❺ add the second solution and record the highest or lowest temperature obtained.
❻ change your independent variable and repeat the experiment.
What is the practical to investigate the variables that affect temperature changes in reacting a solid with a solution such as metal and acid?
❶ place the polystyrene cup inside the glass beaker to make it more stable.
❷ measure an appropriate volume of the solution such as 25cm³.
❸ measure an appropriate mass of the solid or select a suitable sized piece of metal.
❹ place the solution in a polystyrene cup.
❺ record the temperature of the solution.
❻ add the solid and record the highest or lowest temperature obtained.
❼ change your independent variable and repeat the experiment.
