Electrolysis Revision

What happens at the positive electrode?

• Positive non-metal ions are attracted
• Positive metal ions are attracted
• Negative non-metal ions are attracted
• Negative metal ions are attracted

Tags

NGSS.HS-PS2-5

What are produced at positive/negative electrodes during electrolysis of molten NaCI?

• A
• B
• C
• D

What happens at the positive electrode in a voltaic cell and in an electrolytic cell?

• A
• B
• C
• D

What happens when molten NaCI is electrolysed in electrolytic cell?

• Chlorine is produced at positive electrode
• Sodium ions lose electrons at negative electrode
• Electrons flow through liquid from -ve electrode to +ve electrode
• Oxidation occurs at -ve electrode and reduction at +ve electrode

Tags

NGSS.HS-PS1-2

When substance X is electrolysed, the amount of gases P and Q formed is shown.

What is substance X?

• concentrated aqueous sodium chloride

• concentrated hydrochloric acid

• water + acid

• molten lead(II) bromide

What are the electrode products when molten silver iodide is electrolysed between inert electrodes?

• A

• B

• C

• D

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 3V to 6V

• 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 The object turns a reddish-brown colour.

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

3 The copper electrode becomes smaller.

Which statements are correct?

• 1, 2 and 3

• 1 and 2 only

• 1 and 3 only

• 2 and 3 only

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

• chromium

• copper

• silver

• sodium

A student wishes to electroplate an object with copper.

Which row is correct?

• A

• B

• C

• D