Oxidation Numbers Worksheet
A Grade 11 chemistry worksheet covering the rules for assigning oxidation numbers, calculating them in compounds and polyatomic ions, and identifying redox reactions.
Includes
Standards
Oxidation Numbers Worksheet
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Date:
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Read each question carefully and provide the best answer. Show all your work for calculations.
1. State two fundamental rules for assigning oxidation numbers to elements in compounds or polyatomic ions.
2. Assign the oxidation number for each element in the following compounds/ions:
a) H₂O: H = , O =
b) Na₂SO₄: Na = , S = , O =
c) MnO₄⁻: Mn = , O =
d) Cr₂O₇²⁻: Cr = , O =
3. Which of the following reactions is a redox reaction?
HCl + NaOH → NaCl + H₂O
AgNO₃ + KCl → AgCl + KNO₃
2Na + Cl₂ → 2NaCl
CaCO₃ → CaO + CO₂
4. Determine the oxidation number of sulfur in H₂SO₃. Show your calculations.
5. In a redox reaction, a substance that is oxidized gains electrons.
True
False