Chemistry quick practice

Question 1 of 10

The pH of 0.005 mol/dm³ H₂SO₄ (fully ionised) is

Question 2 of 10

Describe how copper is purified by electrolysis. Include the electrodes, the electrolyte, the half-equations and what happens to the impurities.

Question 3 of 10

A current of 3 A flowing for 500 s delivers ___ C of charge.

Question 4 of 10

Calculate the pH of 1 × 10⁻⁴ mol/dm³ sodium hydroxide solution at 25 °C.

Question 5 of 10

Balance the equation Cr₂O₇²⁻ + H⁺ + Fe²⁺ → Cr³⁺ + Fe³⁺ + H₂O by the half-equation method and calculate the moles of Fe²⁺ that react with 0.02 mol of dichromate.

Question 6 of 10

What is the oxidation number of Cl in ClO₃⁻?

Question 7 of 10

Copper(II) compounds are typically

Question 8 of 10

20.0 cm³ of 0.05 mol/dm³ H₂SO₄ neutralises x cm³ of 0.10 mol/dm³ NaOH. Find x.

Question 9 of 10

In a Daniell cell (Zn/Cu), the negative electrode is

Question 10 of 10

PVC is used for water pipes and electrical insulation.