CHEM Test 2 (10th) 21-22

Oxidation state is defined as

• the oxidation of the element being studied

• the number of electrons only gained by the element

• the number of electrons gained or lost by the element

An element in pure state has a oxidation state

• equal to zero

• positive

• negative

The total electrical charge of a molecule is always

• positive

• negative

• zero

The total oxidation state of an element in a compound has to be multiplied by the total number of atoms of the element

• True

• False

 $\sum_{ }^{ }CHARGES=0$  

Explain what this equation means

If oxygen's oxidation state equals -2, calculate lead's oxidation state in

PbO₂

• +4

• +3

• +2

Na oxidation state is

• -1

• +2

• +1

Al oxidation state is

• +3

• -3

• +2

Ca oxidation state is

• +1

• +2

• +3

K oxidation state is

• +1

• -2

• -1