Oxidation Numbers and Carbonate Ions

This video tutorial explains how to determine the oxidation numbers for iron(III) carbonate (Fe2(CO3)3). It begins by introducing the compound as neutral, meaning the oxidation numbers must sum to zero. The video then discusses the oxidation states of iron and the carbonate ion, which is a polyatomic ion with a known charge of 2-. The tutorial demonstrates how to calculate the oxidation numbers for iron using both a direct calculation and an algebraic method, concluding that the oxidation number for iron in this compound is +3.

What is the oxidation number of iron in Fe2(CO3)3?

• +2

• +3

• +6

• +4

Why must the oxidation numbers in a neutral compound add up to zero?

• To balance the charges within the compound

• To ensure the compound is stable

• Because it is a rule for all compounds

• To make the compound reactive

What is the charge of the carbonate ion (CO3)?

• -1

• +2

• -2

• -3

How do oxidation numbers relate to the charge of an ion?

• They are always positive

• They add up to the charge of the ion

• They are always equal

• They are always negative

What is the total oxidation number for three carbonate ions in Fe2(CO3)3?

• -2

• -8

• -4

• -6

What must be the total positive oxidation number to balance the negative charge of the carbonate ions?

• +2

• +6

• +4

• +3

In the algebraic method, what does 'x' represent?

• The total charge of the compound

• The number of iron atoms

• The charge of the carbonate ion

• The oxidation number of iron

What equation is used to find the oxidation number of iron using algebra?

• 2x + 6 = 0

• 2x - 6 = 0

• 2x + (-6) = 0

• 2x + 3 = 0

What is the final oxidation number of iron in Fe2(CO3)3?

• +5

• +4

• +3

• +2

What is the significance of the oxidation number in compounds?

• It shows the reactivity of the compound

• It indicates the stability of the compound

• It helps in balancing chemical equations

• It determines the color of the compound