Redox

Question 1

What is the oxidation number?

Answer 1

A measure of the number of electrons an element uses to bond with another element

Question 2

What does the oxidation numbers sign represent?

Answer 2

How oxidised/ reduced it is

Question 3

What is the oxidation number of any unconvinced element? And give and example

Answer 3

0

E.g 02 Mg Ca N2

Question 4

What is the oxidation number of a simple ion? And give an example

Answer 4

The charge on the ion

E.g Na+ = Na(+1)

Question 5

What is the oxidation number of oxygen in the majority of its compounds?
Give some examples:

Answer 5

-2

H2O, CO2

Question 6

What is the oxidation number of hydrogen in the majority of its compounds and give an example:

Answer 6

+1

HCl H2O

Question 7

What is the total of all oxidation numbers of the elements in a molecule?

Answer 7

0

Question 8

What is the total of all oxidation numbers of the ion in a molecular ion?

Answer 8

The overall charge of the molecular ion

E.g CaCO3^2-

Question 9

What is the total of all oxidation numbers of the ions in an ionic compound?

Answer 9

0

Question 10

What does oxidation and reduction mean in terms of electrons?

Answer 10

Oxidation- loss of electrons

Reduction- gain of electrons

Question 11

How does the oxidation number change to represent change in electrons?

Answer 11

Oxidation number increases- oxidation- loss of electrons

Oxidation number decreases- reduction- gained electrons

Question 12

How do identify the oxidising and reducing agents?

Answer 12

Oxidising agent- removes electrons so is reduced itself

Reducing agent- gives electrons so is oxidised itself

Question 13

How can you tell straight away if it’s REDOX reaction?

Answer 13

There is a single element present as a reactant or product

Question 14

What do redox half equations show?

Answer 14

The change a element or ion with any involved electrons