Chapter 7, Problem 49E

Balance each chemical equation.

a. ${\text{Na}}_2\text{S}\left(aq\right)+\text{Cu}{\left({\text{NO}}_{\text{3}}\right)}_2\left(aq\right)\to {\text{NaNO}}_3\left(aq\right)+\text{CuS}\left(s\right)$

b. $\text{HCl}\left(aq\right)+{\text{O}}_2\left(g\right)\to {\text{H}}_{\text{2}}\text{O}\left(l\right)+{\text{Cl}}_{\text{2}}\left(g\right)$

c. ${\text{H}}_{\text{2}}\left(g\right)+{\text{O}}_2\left(g\right)\to {\text{H}}_{\text{2}}\text{O}\left(l\right)$

d. $\text{FeS}\left(s\right)+\text{HCl}\left(aq\right)\to {\text{FeCl}}_{\text{2}}\left(aq\right)+{\text{H}}_{\text{2}}\text{S}\left(g\right)$