Chemistry P1 - Practicals Flashcards
(3 cards)
1
Q
What’s the practical for making salts?
A
- Measure 20 cm^3 sulfuric acid into a measuring cylinder and pour it into beaker.
- Heat the acid gently using a Bunsen burner.
- Add small amounts of insoluble base in this case copper oxide in excess (until no more
reacts) - Filter using filter paper and funnel the solution to remove the excess copper oxide.
- Pour the solution into the evaporating basin.
- Evaporate the solution using a water bath until crystals start to form.
- Leave the evaporating basin in a cool place for at least 24 hours.
- Gently pat the crystals dry between two pieces of filter paper.
2
Q
What’s the practical for elecryolysis?
A
- Add about 50cm^3 of copper chloride solution to a beaker.
- Add the lid and insert electrodes through the holes making sure the electrodes don’t
touch. - Attach crocodile leads to the electrode and connect the rods to the DC terminals of a low
voltage power supply. - Set the power supply to 4V and switch the power supply on.
- Using the forceps hold the litmus paper near the positive electrode.
- After a few minutes turn the power supply off and observe the negative electrode.
- Record observations at the electrodes.
3
Q
What’s the practical for temperature changes?
A
- Measure 25cm^3 of hydrochloric acid into a polystyrene cup.
- Place the cup inside the beaker to make it more stable.
- Measure and record the temperature of the hydrochloric acid.
- Measure 5cm^3 of sodium hydroxide and add it to the polystyrene cup.
- Quickly put a lid on the cup and gently stir the solution with the thermometer through the
hole of lid. - When the reading on the thermometer stops changing and becomes fairly constant,
record the temperature. - Repeat steps 4 and 5 to add further 5cm^3 amounts of sodium hydroxide to the cup. A
minimum total of 40 cm^3 needs to be added. - Repeat steps 1–7 to ensure reliability of results.
- Calculate the mean maximum temperature reached for each of the sodium hydroxide
volumes
