9 Redox processes

Question 1

Oxidation

Name an example of oxidation and what happens in the process.

Answer 1

2Mg + O₂ –> 2MgO

It is a gain of oxygen or loss of hydrogen.

OR loss of electrons is Oxidation

Question 2

Reduction

Name an example of reduction and what happens in the process.

Answer 2

C₂H₄ + H₂ –> C₂H₆

It is a loss of oxygen or gain of hydrogen.

OR gain of electrons is reduction.

Question 3

What is a redox process?

Answer 3

A red-ox process is when a reduction or oxidation reaction happens.

Question 4

Name a reducing agentand its features.

Name a oxidising agent and its features.

Answer 4

Reducing agent:

reducing agent (also called a reductant or reducer) is an element (such as calcium) or compound that loses (or “donates”) an electron to another chemical species in a redox chemical reaction.

Oxidising agent:

Common oxidizing agents are oxygen, hydrogen peroxide and the halogens. A oxidizing agent (oxidant, oxidizer) is a substance that has the ability to oxidize other substances — in other words to accept their electrons.

Question 5

Name the eight rules of Determining oxidation states.

Answer 5

1. Free elements are given a zero oxidation state.

Question 6

The role of oxidation state in naming species.

For example name the manganese (IV)oxide shows that?

Answer 6

Mn is in the +4 oxidation state in MnO₂

Question 7

Balancing redox hlaf equations.

Name the four steps to balnce a redox half equation.

Answer 7

Atoms 1. Balance the atoms of the oxidation species

Water 2. Balance with H2O on opposite sides

3.

4.

Question 8

Combining half equations

WHat are the 4 steps to combine half equations.

Answer 8

Step.1 Write the two half equations

Step.2 Multiply the equations so that the number of electrons in each is the same

Step.3 Add the two euations and cancel out th eelectrons on either side

Step.4 If necessary, cancel any other species which appear on both sides