Oxidation Numbers and Their Significance

The video tutorial explains how to determine the oxidation numbers for each element in the hydrogen phosphate ion (HPO4 2-). It begins by introducing the concept of oxidation numbers and the significance of the ionic charge. The tutorial then walks through the process of calculating the oxidation numbers for hydrogen, phosphorus, and oxygen, emphasizing that the sum of these numbers equals the ionic charge. The video concludes by solving for the oxidation number of phosphorus, which is determined to be +5, and summarizing the key points discussed.

What is the ionic charge of the hydrogen phosphate ion?

• 2-

• 3+

• 0

• 1+

When hydrogen is bonded to a nonmetal like phosphorus, what is its typical oxidation number?

• +1

• 0

• +2

• -1

What is the usual oxidation number of oxygen in compounds?

• -1

• -2

• 0

• +1

How do the oxidation numbers in a polyatomic ion relate to the ion's charge?

• They are always negative.

• They are always positive.

• They add up to the charge of the ion.

• They are always zero.

What is the oxidation number of phosphorus in the hydrogen phosphate ion?

• +5

• +4

• +3

• +6

If the total oxidation numbers in HPO4 2- add up to -2, what does this indicate?

• The ion is unstable.

• The ion has a charge of +2.

• The ion has a charge of -2.

• The ion is neutral.

What is the significance of the oxidation numbers adding up to the ion's charge?

• It confirms the ion's stability.

• It determines the ion's color.

• It indicates the ion's reactivity.

• It verifies the ion's charge.

Which element's oxidation number was calculated in the video?

• Hydrogen

• Oxygen

• Phosphorus

• Sulfur

What is the role of Dr. B in the video?

• He is a guest speaker.

• He is the narrator explaining the concept.

• He is a student.

• He is a lab technician.