Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A zinc rod of mass g dissolves completely in excess copper(II) sulfate solution. The molar mass of zinc is g/mol and that of copper is g/mol. Find the moles of zinc, the moles of electrons that pass to copper(II) ions, and the mass of copper deposited.
Oxidation is loss of electrons and reduction is gain. The reducing agent gives electrons and is oxidised. The oxidising agent takes electrons and is reduced. Electrons lost equal electrons gained. A stronger reducing agent wins the competition for electrons.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Moles of zinc. mol.
Step 2. Electrons. , so mol of electrons.
Step 3. Copper. uses 2 electrons for each copper atom, so mol of copper forms.
Step 4. Mass. g.
Answer: mol of zinc, mol of electrons, and g of copper.
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