IGCSE Electrolysis and gases

Which of these are required for rusting?

• Iron

• Oxygen

• Water

• Sodium Chloride

What is the definition of the anode?

• The site of oxidation

• The site of reduction

• The negative electrode

• The positive electrode

What colour is magnesium oxide?

(a)  

What colour flame does sulphur burn with?

(a)  

What percentage of the atmosphere is oxygen gas?

(a)  

What percentage of the atmosphere is carbon dioxide?

(a)  

What is the name of a piece of magnesium attached to the hull of a ship to prevent corrosion?

(a)  

In this set up, which way are the electrons flowing?

• clockwise

• anticlockwise

Electrolysis of a substance produces iodine at the anode and magnesium at the cathode. What could the substance be?

• Aqueous magnesium iodide

• Molten magnesium iodide

Which of these would you see during the electrolysis of copper sulphate?

• A gas given off at the anode.

• A gas produced at the cathode.

• A pink brown deposit at the cathode

• The solution becoming cloudy