What happens when you put magnesium in a copper(II) chloride solution?

Question

This is supposed to be a single displacement reaction, and there was a forming of copper.

But the solution is supposed to be magnesium chloride, which is supposed to be colourless and transparent.

Instead, the solution formed in our experiment was light green and opaque. What happened?

Answer 1

Sounds like you still had copper ions in solution after you ran out of magnesium.