Redox practice

Oxidation states for

CaCrO₄

• Ca=+2, Cr=+6, O=-2

• Ca=+2, Cr=+4, O=-2

• Ca=+2, Cr=+6, O=-8

• Ca=+4, Cr=+6, O=-2

Oxidation states for CO₃^2-

• C=+4, O=-6

• C=+4, O=-2

• C=+6, O=-2

• C=+2, O=-2

Oxidation states for

NaBr

• Na=+1, Br=-1

• Na=+1, Br=-7

• Na=+2, Br=-2

• Na=+1, Br=-2

Oxidation states for

S₂O₄

• S=-4, O=-2

• S=+4, O=-2

• S=+4, O=-8

• S=+8, O=-8

Oxidation state for

I₂

• I=-1

• I=0

• I=+7

• I=-2

Total sum of charges on a compound

• zero

• one

• two

• three

Tags

NGSS.HS-PS1-7

Oxidation state for magnesium metal in a compound

• 0

• +1

• +2

• -2

Which is oxidized and which is reduced?

Ca + Na₂O → Na + CaO

• Oxidized: Na Reduced: O

• Oxidized: Ca Reduced: O

• Oxidized: Na Reduced: Ca

• Oxidized: Ca Reduced: Na

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which is oxidized and which is reduced?

CaCl₂ + O₂ → CaClO₃

• Oxidized: Ca Reduced: O

• Oxidized: Cl Reduced: O

• Oxidized: Ca Reduced: Cl

• Oxidized: O Reduced: Cl

Tags

NGSS.HS-PS1-7

WRITE THIS OUT ON PAPER, YOU MAY USE THE ANSWER TO THIS PROBLEM AGAIN IN ANOTHER QUESTION:

Balance the following ACIDIC reactions using the half-reaction method.

MnO₄⁻(aq) + I⁻ (aq) → Mn²⁺(aq) + I₂(s)

Water is a product of this reaction. What is the coefficient of water in the final balanced equation?

• 8

• 5

• 2

• 16