Oxidation Numbers

The sum of all oxidation numbers in a neutral compound is ___.

• 0
• 1
• -1
• depends on the compound

What is the oxidation of C in CH₄?

• -4
• -1
• +4
• +1

What is oxidation number of Mn in MnO₂ ?

• 0
• +2
• -2
• +4

What is the oxidation number of Ca in Ca₃N₂?

• +3
• +2
• -3
• -2

What is oxidation number of Cr in
Cr₂O₇^2-?

• -2
• +2
• +6
• +12

What is oxidation number of P in K₃PO₄?

• +1
• +5
• -2
• 0

What are oxidation numbers?

• Number of electrons in the outer most energy level
• Number of protons
• Electrons gained or lost in chemical bonding
• Number of neutrons gained or lost

What are valence electrons?

• Number of electrons in the outer most energy level
• Number of electrons gained or lost
• Number of electrons in the inner energy level
• Number of electrons 

What is the oxidation number of Fe in FeO?

• +1
• -1
• +2
• -2

What is the oxidation number of O in CO₂?

• +2
• -1
• +4
• -2