3

Question 1

What is an oxidation number?

Answer 1

The number of electrons an atom uses to bond with any other atom

Question 2

Define oxidation in terms of electron transfer and oxidation number

Answer 2

Oxidation is
● Loss of electrons
● An increase in oxidation number

Question 3

Define reduction in terms of electron transfer and oxidation number

Answer 3

Reduction is
● Gain of electrons
● A decrease in oxidation number

Question 4

What is a redox reaction?

Answer 4

A reaction in which both oxidation and reduction takes place

Question 5

What is the oxidation number of an uncombined element such as C, H, O2?

Answer 5

0

Question 6

What is the oxidation number of group 1 elements?

Answer 6

+1

Question 7

What is the oxidation number of group 2 elements?

Answer 7

+2

Question 8

What is the oxidation number of aluminium?

Answer 8

+3

Question 9

What is the oxidation number of fluorine?

Answer 9

-1

Question 10

What is the oxidation number of the rest of the group 7 elements?

Answer 10

-1

Unless they are bonded with fluorine, then it is +1

Question 11

What is the oxidation number of hydrogen?

Answer 11

+1

Unless they are in a metal hydride, then it is -1

Question 12

What is the oxidation number of oxygen?

Answer 12

-2

Unless they are in peroxides, then it is -1

Question 13

What is the oxidation number of oxygen in peroxides?

Answer 13

-1

Question 14

What is the oxidation number of hydrogen in metal hydrides such as LiH?

Answer 14

-1

Question 15

What is the oxidation number of a simple ion?

Answer 15

Charge on the ion

E.g Na+ → +1 ; Cl- → -1

Question 16

When an element has more than one stable oxidation number how is it indicated?

Answer 16

Written as a Roman numeral

Question 17

What is the oxidation number of Fe in iron (III) chloride?

Answer 17

+3

Question 18

What are oxyanions?

Answer 18

Negative ions that have an element along with oxygen

Question 19

What is the oxidation number of a metal?

Answer 19

0, because it is an uncombined element

Question 20

What is an oxidising agent?

Answer 20

Species that gains electrons

It oxidises something and is reduced itself

Question 21

What is a reducing agent?

Answer 21

Species that lose electrons.

It reduces something and is oxidised itself

Question 22

Define the term disproportionation?

Answer 22

Where in a redox reaction, the oxidation states of atoms of the same element, increase for some atoms, whereas decrease for some atoms.

A reaction in which a substance is simultaneously oxidized and reduced, giving two different products