redox reactions

What element is being Oxidized?

• N
• H
• O
• S

Is calcium oxidized or reduced in the following reaction? 
2 CaO--> 2 Ca + O₂

• Oxidized
• Reduced

Which of the following half reactions correctly represents a reduction half reaction?

• Fe →Fe²⁺ + 2e^-
• Pb⁴⁺ + 2e^- →Pb²⁺
• 2O^-2 →O₂ + 4e^-
• Fe + 3e^- →Fe³⁺

What is the oxidation number of chlorine in HClO?

• 0

• -1

• +1

• +5

Reduction is the ___________ of electrons.

• loss

• gain

• sharing

• transfer

What is the oxidation number of iodine in KIO₃?

• 0

• -1

• +5

• +1

Determine the oxidation number of chromate in CrO₄^2-.

• +6

• 0

• +2

• +3

Which of the following represents oxidation?

• C → CH₄

• Fe³⁺ → Fe²⁺

• Cl₂ → 2Cl^-

• Zn → ZnO

In the reaction Zn + 2HCl --> ZnCl₂ + H₂

which element, if any, is oxidized?

• Zinc

• Hydrogen

• Chlorine

• None

Which statement is true:
Mg → Mg²⁺ + 2e^–

• Mg gains 2 electrons
• Mg_²⁺ loses 2 electrons
• Mg loses 1 electron
• Mg loses 2 electrons