Preparation of copper(II) sulfate crystals

1. Name the apparatus used to measure 5cm³ dilute sulfuric acid in Step 1.

• Conical flask

• Beaker

• Measuring cylinder

• Test tube

2. Name the base used in this experiment.

• copper(I) oxide

• copper(II) oxide

• copper

• dilute sulfuric acid

3. Why is the dilute sulfuric acid heated gently in Step 1?

• to form a saturated solution

• to prevent thermal decomposition of the salt

• to remove excess salt solution

• to speed up the reaction

4. Why is filtration done in Step 4?

• to remove excess copper(II) oxide

• to remove excess copper(II) sulfate

• to remove sand

• to filter out the acid

5. In Step 3, copper(II) oxide is added to dilute sulfuric acid in excess. How to ensure that the copper(II) oxide added is already in excess?

• when the solution turns blue

• when the copper(II) oxide can no longer dissolve in the acid

• when the copper(II) sulfate can no longer dissolve in the acid

• just by instinct