Chemistry 0620 · IGCSE · Electrolysis

Electrolysis — practice question

(a)[2]

Calculate the empirical formula of the hydrated nickel(II) iodide crystals.

(b(i))[1]

Name the type of particles which carry charge through the copper wires.

(b(ii))[1]

Name the type of particles which carry charge through the molten nickel(II) iodide.

(b(iii))[3]

Predict the products of the electrolysis of molten nickel(II) iodide. Write an ionic half-equation for the formation of one of these products.

(c(i))[1]

Explain why the mass of the negative electrode increased in both sets of apparatus.

(c(ii))[1]

Name the gas that formed the bubbles seen in apparatus A.

(c(iii))[1]

Explain why the mass of the positive electrode decreased in apparatus B.

(c(iv))[3]

Suggest what happens to the colour of the solution in apparatus A and apparatus B as the electrolysis progresses. Explain your answer. colour of the solution in apparatus A colour of the solution in apparatus B explanation

Worked solution & mark scheme

This 13-mark question has a full step-by-step worked solution and mark scheme. One marking point: Accurate molar ratios/calculations

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI