Electroplating

If the electrode is not inert, the one that will be oxidised is the ... itself.

Which electrode is classified as inert?

• Copper

• Iron

• Graphite

• Tin

Which statement below is correct about metal refining?

• Impure metal should be put in cathode

• Pure metal is put in anode

• Metal will be transferred from cathode to anode

• Metal will be transferred from anode to cathode

Which one is not the benefit of electroplating?

• Prevent corrosion

• Improve its appearance

• Make it a better electrical conductor

• Hold their value over time

A metallic object is electroplated with copper using a solution of copper(II) sulfate. Which statement is correct?

• The positive electrode increases in mass.

• The concentration of Cu²⁺ ions in the solution decreases.

• Reduction occurs at the positive electrode.

• The reaction occurring at the negative electrode is Cu²⁺ + 2e^– --> Cu.

Which are used for the electroplating of a metal spoon with Copper?
I. an electrolyte containing aqueous Copper(II) ions

II. a Copper anode (positive electrode)

III. a Copper cathode (negative electrode)

• I and II only

• I and III only

• II and III only

• I, II and III

The diagram shows a failed attempt to copper-plate a pan.

Which action will plate the pan with copper?

• Cooling the copper sulfate solution in an ice bath

• Heating the copper sulfate solution to boiling point

• Increasing the voltage from 3 V to 6 V

• Making the pan the cathode and the copper the anode

The diagram shows the electroplating of a steel object.

A student made the following statements.

1. 1. The object turns a reddish-brown colour.

2. 2. The copper sulfate solution changes to a paler blue colour.

3. 3. The copper electrode becomes smaller.

4. Which statements are correct?

• 1, 2 and 3

• 1 and 2 only

• 1 and 3 only

• 2 and 3 only

An object is electroplated with silver using an aqueous silver salt as the electrolyte. Which set of conditions is used?

• A

• B

• C

• D

Which metal could not be used for electroplating by using an aqueous solution?

• Chromium

• Copper

• Silver

• Sodium