Oxidation States in Compounds

This video tutorial explains oxidation numbers, focusing on how to determine them for elements, ions, and compounds. It covers the rules for pure elements, ions, and compounds, emphasizing the role of electronegativity. The tutorial includes examples and calculations for various elements and compounds, such as zinc, magnesium, and polyatomic ions like sulfate and phosphate. It also discusses the concept of average oxidation states in complex ions.

What is the oxidation state of a pure element?

• Always negative

• Always zero

• Depends on the element

• Always positive

How is the oxidation state of a monoatomic ion determined?

• By its atomic number

• By its position in the periodic table

• By its charge

• By its mass

What is the typical oxidation state of fluorine in compounds?

• +1

• +2

• -1

• 0

In a compound, what oxidation state does hydrogen usually have when bonded to a non-metal?

• -1

• +2

• +1

• 0

What is the oxidation state of vanadium in vanadium oxide (V2O5)?

• +3

• +6

• +4

• +5

In the sulfate ion (SO4^2-), what is the oxidation state of sulfur?

• +4

• +6

• +2

• +8

What is the oxidation state of nitrogen in nitrate (NO3^-)?

• +3

• +5

• +1

• +4

Which element is more electronegative, oxygen or fluorine?

• Oxygen

• Fluorine

• They are equal

• Depends on the compound

In sodium hydride (NaH), what is the oxidation state of hydrogen?

• 0

• -1

• +1

• +2

What is the average oxidation state of iron in Fe3O4?

• +3

• +2

• +2.67

• +4