Question

Reduction Reaction Question

When metal A is placed in a solution of a salt of metal B, the surface of metal A changes color. When metal B is placed in acid solution, gas bubbles form on the surface of the metal. When metal A is placed in a solution of a salt of metal C, no change is observed in the solution or on the surface of metal A.

(a) Will metal C cause formation of H2 when placed in acid solution? My reasoning: Nope, because there is no evidence of an oxidation reaction, meaning that C is less likely to cause a reaction.

(b) Rank metals A, B, and C in order of decreasing reducing strength. My reasoning: B>A>C, since C is the one that didn't react with anything, it must have the lowest reducing strength.

What does the color change of A in Salt of B indicate? I thought that it was an oxidation reaction.