Oxidation States

Oxidation States

Oxidation Number Rules-1

• Pure elements have an oxidation number of Zero

• It doesn't matter how many atoms there are

Multiple Choice

What is the oxidation number of S₈?

• 0

• 8

• 6

• 16

Oxidation Number Rules- 2

• In a Binary Molecular Compound

• -the more electronegative element gets the charge it would have as an anion

• i.e Flourine would have an oxidation number of 1-

• The less electronegative gets the charge it would have as a cation

Multiple Choice

In NCl₃, Chlorine has an oxidation number of

• 1-

• 1+

• 3-

• 3+

Multiple Choice

In NCl₃, Nitrogen has and oxidation Number of

• 3-

• 3+

• 1-

• 1+

Oxidation Number Rules-3

• Flourine always has and oxidation Number of -1 in its compounds

Multiple Choice

In CF₄, Flourine has an oxidation number of

• -4

• +4

• -1

• +1

Oxidation Number Rules- 4

• Oxygen has an oxidation number of -2

• Exception 1: Peroxide formations, H₂O₂- here it is -1

• Exception 2: it is bonded with flourine

Multiple Choice

In OF₂ what is Oxygens Oxidation Number?

• +2

• -2

• +1

• -1

Multiple Choice

In CO_2, oxygen has an oxidation number of what?

• -2

• +2

• -1

• +1

Oxidation Number Rules-5

• Hydrogen has an oxidation number of +1 in all compounds containing elements that are more electronegatice

• It has a -1 with all metals

Multiple Choice

In H₂O₂, hydrogen has an oxidation number of

• +1

• -1

• +2

• -2

Multiple Choice

In LiH, hydrogen has an oxidation number of

• -1

• +1

• -2

• +2

Rules- 6&7

• Sum of the oxidation numbers in a neutral compound must equal zero

• Sum of Oxidation Numbers in a polyatomic ion is equal to its charge

Multiple Choice

In ClO₃^-, what is chlorine's oxidation number?

• +5

• -5

• +2

• +6

Rule 8

• In a monatomic ion, the oxidation number is equal to the charge it would have as an ion.

Multiple Choice

Ca²⁺ has an oxidation number of

• +2

• -2

• +1

• -1

Multiple Choice

Choose the correct oxidation numbers for HCl

• -1,+1

• +1,-1

• +2,-2

• -2,+2

Multiple Choice

Choose the oxidation numbers for each atom in P₄O₁₀

• +5, -2

• -5,+2

• +2,-5

• -2,+5

Multiple Choice

Assign oxidation numbers to each atom in HClO₃

• +1, +5, -2

• +1, -5, -2

• +1, -3, -2

• -1, +5, -2