Oxidation Numbers and Ionic Compounds

The video tutorial explains how to find oxidation numbers for each element in ammonium carbonate (NH4)2CO3. It breaks down the compound into its ions: ammonium (NH4+) and carbonate (CO3^2-). For the ammonium ion, the oxidation number of nitrogen is calculated as -3, while each hydrogen is +1. For the carbonate ion, the oxidation number of carbon is determined to be +4, with each oxygen being -2. The tutorial concludes by verifying the oxidation numbers add up to the ionic charges.

What is the overall charge of ammonium carbonate?

• Positive

• Neutral

• Negative

• Variable

How many ammonium ions are present in ammonium carbonate?

• Four

• One

• Three

• Two

What is the oxidation number of nitrogen in the ammonium ion?

• +3

• +1

• -3

• -1

What is the oxidation number of hydrogen in the ammonium ion?

• -1

• +1

• +2

• 0

What is the charge of the carbonate ion?

• 0

• +2

• -2

• -1

What is the oxidation number of carbon in the carbonate ion?

• -4

• +2

• 0

• +4

What is the oxidation number of oxygen in the carbonate ion?

• -1

• 0

• -2

• +2

How many oxygen atoms are present in the carbonate ion?

• One

• Two

• Four

• Three

What is the total oxidation number for the three oxygen atoms in the carbonate ion?

• -6

• -3

• -2

• -4

What is the purpose of finding oxidation numbers in compounds?

• To determine the physical state

• To calculate molecular weight

• To predict chemical reactions

• To find the melting point