Oxidation State and number.

Complete the questions 1-9 on page 6 of this worksheet. Show all your working out. There is plenty of worked example from page 1-5 on the worksheet, but visit chemguide or ask for help if required.
In each of the following chemicals, determine the oxidation states of each element. Where appropriate, state whether the reaction is oxidation, reduction, redox, or neither.

1) sodium nitrate

2) ammonia

3) zinc oxide

4) water

5) calcium hydride

6) carbon dioxide

7) nitrogen

8) sodium sulfate

9) aluminum hydroxide

10) magnesium phosphate


In each of the following reactions, determine what was oxidized and what was reduced.

11) Ca + H2O --> CaO + H2

Element oxidized: ____________________________________

Element reduced: ____________________________________

12) 2H2 + O2 --> 2H2O

Element oxidized: ____________________________________

Element reduced: ____________________________________
13) CaCO3 --> CaO + CO2
Element oxidized: ____________________________________
Element reduced: ____________________________________
14) CaO + H2O --> Ca(OH)2

Element oxidized: ____________________________________

Element reduced: ____________________________________

15) Ca(OH)2 + 2CO2 --> Ca(HCO3)2

Element oxidized: ____________________________________

Element reduced: ____________________________________

16) What is the difference between an oxidation state and an oxidation number?