Suppose you wanted to cause Ni²⁺ ions to come out of solution as solid Ni. Which metal could you use to accomplish this?

• A. Au
• B. Sn
• C. Mn
• D. Ag
• E. Cu

Answer: (C)

Verified step by step guidance

1. Understand the concept of reduction potential: Metals can cause ions to come out of solution based on their reduction potential. A metal with a lower reduction potential can reduce ions of a metal with a higher reduction potential.
2. Identify the reduction potential of Ni2+ ions: Nickel ions (Ni2+) have a specific reduction potential, which can be found in standard reduction potential tables.
3. Compare reduction potentials: Look up the reduction potentials for each of the metals listed (Au, Sn, Mn, Ag, Cu) and compare them to the reduction potential of Ni2+.
4. Determine which metal can reduce Ni2+: The metal that has a lower reduction potential than Ni2+ can donate electrons to Ni2+ ions, causing them to be reduced to solid Ni.
5. Select the appropriate metal: Based on the comparison, identify which metal has a lower reduction potential than Ni2+ and can therefore cause Ni2+ ions to come out of solution as solid Ni.