Oxidation Reduction Numbers and Half Reactions

In redox reactions, we look at the movement of...

• Protons

• Neutrons

• Electrons

• Charge

An atom that undergoes oxidation...

• Loses electrons

• Gains electrons

• Does not change it's electron count

Tags

NGSS.HS-PS1-1

What is a spectator ion?

• An ion that undergoes oxidation

• An that undergoes reduction

• An ion not involved in the redox reaction

The reductant...

• undergoes reduction, and causes the other species to become oxidised.

• undergoes oxidation, and causes the other species to become reduced.

• undergoes reduction, and causes the other species to become reduced.

• undergoes oxidation, and causes the other species to become oxidised.

In the half equation:

Cu --> Cu²⁺ + 2e^-

Copper undergoes...

• Spectatorship

• Reduction

• Deprotonation

• Oxidation

In the redox equation:

Zn + CuSO₄ --> ZnSO₄ + Cu

SO₄^2- acts as...

• an Oxidant

• a Reductant

• a Spectator Ion

The reaction:

NaCl + AgNO₃ --> AgCl + NaNO₃

is not a redox reaction because...

• AgCl precipitates as a solid compound.

• there is no change in oxidation number for any ions present.

• Polyatomic ions cannot be involved in redox reactions.

• Trick Question! It is a redox reaction!

If the oxidation number of an element reduces in a redox reaction, then this corresponds to the process of...

• Reduction

• Oxidation

What is the oxidation number of Mg in MgCl₂ (Magnesium Chloride)?

• +1

• +2

• -1

• -2

Which of the following halogens always has an oxidation number of -1?

• Iodine

• Bromine

• Chlorine

• Fluorine