Oxidation Numbers and Hydroxide Ion

The video tutorial explains how to determine the oxidation numbers for each element in lithium hydroxide (LiOH). It starts by identifying LiOH as a neutral compound, meaning the oxidation numbers must sum to zero. The hydroxide ion (OH-) has a charge of -1, which helps determine that lithium must have a positive oxidation number. The video further explains that oxygen typically has an oxidation number of -2, and hydrogen is +1. By adding these values, the oxidation numbers for LiOH are confirmed to sum to zero. The tutorial concludes with a recap of these calculations.

What is the total sum of oxidation numbers in a neutral compound like LiOH?

• It is always positive.

• It is equal to the number of elements.

• It is always zero.

• It equals the charge of the compound.

What is the charge of the hydroxide ion in LiOH?

• 1-

• 1+

• 2-

• 2+

Given the hydroxide ion's charge, what must be the oxidation number of lithium in LiOH?

• 0

• 1+

• 1-

• 2+

What is the typical oxidation number assigned to oxygen in compounds?

• 1+

• 2-

• 0

• 1-

What is the oxidation number of hydrogen in most compounds?

• 1-

• 0

• 1+

• 2-

In LiOH, what is the sum of the oxidation numbers of lithium, oxygen, and hydrogen?

• 2-

• 0

• 1-

• 1+