Oxidation Numbers and Ionic Charges

The video tutorial explains how to determine oxidation numbers for elements in ammonium nitrate (NH4NO3). It begins by discussing the rules for oxidation numbers in neutral molecules and ions. The tutorial then calculates the oxidation number for nitrogen in the ammonium ion (NH4) and the nitrate ion (NO3), showing that nitrogen has different oxidation numbers in each ion due to its bonding with hydrogen and oxygen, respectively. The video concludes with a summary of the oxidation numbers for each element in NH4NO3.

What is the sum of oxidation numbers in a neutral molecule?

• It is always positive.

• It is always zero.

• It is always negative.

• It equals the charge of the molecule.

What is the charge of the ammonium ion?

• Minus one

• Plus two

• Plus one

• Zero

What is the oxidation number of the nitrate ion?

• Minus two

• Plus two

• Minus one

• Plus one

How many hydrogen atoms are bonded to nitrogen in the ammonium ion?

• Five

• Four

• Two

• Three

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

• Minus five

• Plus three

• Minus three

• Plus five

What is the oxidation number of oxygen in most compounds?

• Minus one

• Zero

• Minus two

• Plus two

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

• Minus five

• Plus five

• Plus three

• Minus three

Why does nitrogen have different oxidation numbers in ammonium and nitrate ions?

• Because it is bonded to different elements.

• Because it is a transition metal.

• Because it has a variable charge.

• Because it is in a different state of matter.

What must be considered when calculating oxidation numbers?

• The color of the compound

• The context of the bonds

• The phase of the compound

• The temperature of the reaction

What is the overall charge of ammonium nitrate?

• Zero

• Plus two

• Minus one

• Plus one