Oxidation Numbers in Al2S3

The video tutorial explains how to determine the oxidation numbers for each element in aluminum sulfide (Al2S3). It begins by noting that Al2S3 is a neutral compound, meaning the oxidation numbers must sum to zero. The tutorial then explains how to assign oxidation numbers based on electronegativity and ionic charges, specifically focusing on sulfur's -2 charge and aluminum's +3 charge. The video concludes by verifying that the calculated oxidation numbers result in a neutral compound.

What is the overall charge of a neutral compound like Al2S3?

• Depends on the elements

• Zero

• Negative

• Positive

How do we determine the oxidation number of sulfur in Al2S3?

• By its position in the periodic table

• By its ionic charge as an ion

• By the number of sulfur atoms

• By the charge of aluminum

What is the oxidation number of each sulfur atom in Al2S3?

• +2

• -2

• +1

• -1

How do we calculate the total oxidation number for sulfur in Al2S3?

• Divide the oxidation number of sulfur by the number of aluminum atoms

• Subtract the oxidation number of aluminum from sulfur

• Multiply the oxidation number of sulfur by the number of sulfur atoms

• Add the oxidation numbers of sulfur and aluminum

What oxidation number must aluminum have to balance the compound Al2S3?

• +3

• +2

• +4

• +1

What is the oxidation number of each aluminum atom in Al2S3?

• +4

• +1

• +2

• +3

Why do the oxidation numbers in Al2S3 add up to zero?

• Because it is a charged compound

• Because aluminum has a lower oxidation number

• Because it is a neutral compound

• Because sulfur has a higher oxidation number