Addition of iron or zinc to copper sulphate cause, precipitation of copper owing to the:

Zinc powdern is added to copper sulphate solution.

When iron rod is immersed in copper sulphate solution.

A student performed following two activities in school laboratory: Activity 1: Addition of zinc dust into copper sulphate solution taken in a test tube. Activity 2: Addition of an iron nail into copper sulphate solution taken in a test tube. He noted down his observations and concluded that chemical reaction occurs in both the cases based on the observed colour change of the resulting solution. Based on these activities, what can you conclude about the reactivity of elements zinc and iron as compared to that of copper?

Addition of zinc powder to CuSO-4 solution precipitates copper due to :