Question

The following redox reaction can occur between zinc (Zn) and copper (Cu): Zn(s) + CuSO4(aq) → ZnSO4(aq) +Cu(s) The transfer of electrons that occurs in this reaction can be exploited to create a battery. A. Write the net ionic equation for this reaction. B. Which atoms or ions are reduced in the reaction? Which are oxidized? C. How many electrons are transferred from each oxidized atom (or ion) to each reduced atom (or ion) in the reaction? D. If 100 mL of a 1.5 M solution of CuSO4 is used and fully reacted with excess solid zinc, how many electrons were transferred in the process?

Answer 1

Zn(s)   + CuSO4(aq) --------------------> ZnSO4(aq) + Cu(s)

here the Zn is converted into the ZnSO4

the CuSO4 is converted into the Cu

A) net ionic equation is as follows

Zn(s) + Cu²⁺ (aq) --------------------------------> Zn²⁺ (aq)   + Cu(s)

B) Zn is changed into the Zn²⁺ i.e increase in oxidation number so it is oxidised

Cu is changed into the Cu²⁺ i.e decrease in oxidation number so it is reduced

C) here Zn is having the charge 0 & the Zn²⁺ i.e the charge is +2 so two electrons are transfered

so in each oxidised and reduced atom shows the two electrons transferred

D) no of moles of CuSO4 => 0.1 L * 1.5 M => 0.15 moles

for 1 mole -----------------> 2 electrons

0.15 moles ---------------> ?

=> 0.15 * 2 => 0.3 moles of electrons are transferred