For variable metals in products, assume they chose 2+ charge.
If the following single replacement reactions will occur, write and balance them. If not, write NR
a. Pb + Sn(NO3)2
b. H2 + NiSO4
c. Cr + Ni(NO2)2
d. H2 + Au PO4
Spontaneous oxidation-reduction reactions convert the stronger of a pair of oxidizing agents and the stronger of a pair of reducing agents into a weaker oxidizing agent and a weaker reducing agent.
a. Pb + ...
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