4E ScChem Chp 12 Redox TYS MCQ

Which row describes what happens during an oxidation reaction?

• A

• B

• C

• D

Answer explanation

Oxidation involves loss of hydrogen and/or loss of electrons (OiL)

Which statement describes oxidation?

• Electrons are gained and the oxidation state decreases.

• Electrons are gained and the oxidation state increases.

• Electrons are lost and the oxidation state decreases.

• Electrons are lost and the oxidation state increases.

Answer explanation

Oxidation involves loss of electrons and increase in oxidation state.

Which change represents oxidation?

Answer explanation

Zn loses 2 electrons to form Zn²⁺, hence Zn is oxidised.

OR

The oxidation state of Zn increases from 0 to +2, hence Zn is oxidised.

In which reaction is the underlined substance reduced?

Part of some chemical reactions are shown.

Which reaction represents oxidation?

• C

• Fe₂O₃

• CO

• Fe

Substance X turns a solution of acidified potassium manganate(VII) from purple to colourless.

What must solution X contain?

• an alkali

• an ammonium salt

• an oxidising agent

• a reducing agent

• The iron(II) chloride is an oxidising agent and is oxidised.

• The iron(II) chloride is an oxidising agent and is reduced.

• The iron(II) chloride is a reducing agent and is oxidised.

• The iron(II) chloride is a reducing agent and is reduced.

• CuO
• C
• Cu
• CO2

• Fe
• Cu2+
• Cu
• Fe2+