Question

Write a balanced molecular equation for the reaction of each of the following metals with aqueous NiCl2. If no reaction occurs, put NR. (a) Zn (b) Cu (c) Cr (d) Pb

Answer 1

standard reduction potentials

Zn = -0.76 V

Cu = +0.34 V

Cr = -0.91 V

Pb = -0.13 V

Ni = -0.26 V

lower reduction potential element will be higher active . higher active can replace lower acitve

a)   Zn   + NiCl2 ------------------> Ni    + ZnCl2

b)    Cu + NiCl2 --------------------> no reaction (NR)

c) Cr + NiCl2 -----------------> Ni   + CrCl2

d)   Pb + NiCl2 -----------------> no reaction (NR)