Chemistry: Quiz: Oxidation Numbers

Quiz: Oxidation Numbers

1. When a neutral atom loses an electron, the ion which is formed has

a. a positive charge

b. a negative charge

c. no charge

2. In the formation of ions, electrons are

a. transferred from one atom to another atom

b. shared between two atoms

c. removed from both atoms

3. The oxidation number of any free element is

a. positive

b. zero

c. negative

4. The oxidation number of sulfur in H₂SO₄ is

a. –2

b. 0

c. +6

5. The oxidation number of any alkali metal ion is

a. –2

b. 0

c. +1

6. The oxidation number of oxygen in the compound CaO is

a. +3

b. –1

c. –2

7. The oxidation number of nitrogen in equation

a. –3

b. +3

c. +5

8. When assigning oxidation numbers to elements in a compound, the sum of all the charges must equal

a. a positive value

b. zero

c. a negative value

9. When assigning oxidation numbers to elements in covalent compounds, the __________ will have the negative oxidation number.

a. more metallic element

b. diatomic element

c. more electronegative element