Oxidation Numbers and Phosphate Ions

The video tutorial explains how to determine the oxidation numbers for each element in aluminum phosphate (AlPO4). It begins by discussing the concept of oxidation numbers in neutral compounds, where the sum of oxidation numbers equals zero. The video then identifies the oxidation number of aluminum as +3 and explains the charge of the phosphate ion (PO4) as -3. Finally, it calculates the oxidation number of phosphorus as +5, ensuring the compound remains neutral.

What is the overall charge of a neutral compound?

• Depends on the elements

• Zero

• Negative

• Positive

What is the typical oxidation number for aluminum in compounds?

• +1

• +2

• 0

• +3

What is the charge of the phosphate ion (PO4)?

• -3

• 0

• -2

• -1

How many oxygen atoms are present in the phosphate ion?

• 2

• 5

• 3

• 4

What is the usual oxidation number for oxygen in compounds?

• -2

• -1

• +1

• 0

In the equation to find phosphorus's oxidation number, what is the sum of the oxidation numbers supposed to equal?

• 0

• 2

• 1

• -1

What is the oxidation number of phosphorus in aluminum phosphate?

• +6

• +5

• +4

• +3

Which element in aluminum phosphate has an oxidation number of +3?

• Hydrogen

• Aluminum

• Oxygen

• Phosphorus

What is the total oxidation number for the four oxygen atoms in the phosphate ion?

• -10

• -6

• -8

• -4

What is the purpose of calculating oxidation numbers in compounds?

• To determine the color of the compound

• To measure the temperature of the compound

• To find the stability of the compound

• To understand electron transfer in reactions