Chapter 7, Problem 83E

Which reactions are redox reactions?

a. $\text{Ba}{\left({\text{NO}}_{\text{3}}\right)}_2\left(aq\right)+{\text{K}}_{\text{2}}{\text{SO}}_{\text{4}}\left(aq\right)\to {\text{BaSO}}_{\text{4}}\left(s\right)+2{\text{ KNO}}_{\text{3}}\left(aq\right)$

b. $\text{Ca}\left(s\right)+{\text{Cl}}_{\text{2}}\left(g\right)\to {\text{CaCl}}_{\text{2}}\left(s\right)$

c. $\text{HCl}\left(aq\right)+\text{NaOH}\left(g\right)\to {\text{H}}_{\text{2}}\text{O}\left(l\right)+\text{NaCl}\left(aq\right)$

d. $\text{Zn}\left(s\right)+{\text{Fe}}^{\text{2+}}\left(aq\right)\to {\text{Zn}}^{\text{2+}}\left(aq\right)+\text{Fe}\left(s\right)$