Question #06667

1 Answer
Jun 23, 2015

#AgCl + 2NH_4OH -> [Ag(NH_3)_2]Cl + 2H_2O#

Explanation:

The trick here is to realize that ammonium hydroxide, #NH_4OH#, is actually ammonia, #NH_3#, dissolved in water.

#NH_(3(aq)) + H_2O_((l)) rightleftharpoons NH_(4(aq))^(+) + OH_((aq))^(-)#

If you write the complete ionic equation for this reaction, you'll get

#AgCl_((s)) + NH_(3(aq)) + cancel(H_2O_((l))) -> [Ag(NH_3)_2]Cl + cancel(H_2O_((l)))#

The net ionic equation for this reaction is

#AgCl_((s)) + NH_(3(aq)) -> overbrace([Ag(NH_3)_(2(aq))]^(+))^(color(blue)("diamminesilver (I))) + Cl_text((aq])^(-)#

The ammonia reacts with the silver cations to form the diamminesilver (I) metal complex. To balance this equation, simply multiply the ammonia molecules present on the reactants' side by 2.

#AgCl_((s)) + 2NH_(3(aq)) -> [Ag(NH_3)_(2(aq))]^(+) + Cl_text((aq])^(-)#

To get the initial equation balanced, simply multiply #NH_4OH# by 2.

#AgCl + 2NH_4OH -> [Ag(NH_3)_2]Cl + H_2O#

Finally, balance the hydrogen and oxygen atoms by multiplying the water molecule present on the products' side by 2.

#AgCl + 2NH_4OH -> [Ag(NH_3)_2]Cl + 2H_2O#

And that's how the balanced chemical equation looks like.