Question #a1fd3

1 Answer
Aug 29, 2017

Answer:

#"CaSO"_ (3(s)) + 2"H"_ ((aq))^(+) -> "Ca"_ ((aq))^(2+) + "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#

Explanation:

Calcium sulfite, #"CaSO"_3#, will react with hydrochloric acid, #"HCl"#, to produce aqueous calcium chloride, #"CaCl"_2#, and sulfurous acid, #"H"_2"SO"_3#.

However, sulfurous acid does not exist in aqueous solution as a molecule, it actually decomposes to form sulfur dioxide, #"SO"_2#, and water.

You can thus say that the balanced chemical equation that describes this reaction looks like this

#"CaSO"_ (3(s)) + 2"HCl"_ ((aq)) -> "CaCl"_ (2(aq)) + color(red)(cancel(color(black)("H"_ 2"SO"_ (3(aq)))))#

#color(white)(aaaaaaaaa)color(red)(cancel(color(black)("H"_ 2"SO"_ (3(aq))))) -> "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#
#color(white)(aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)/color(white)(a)#

#"CaSO"_ (3(s)) + 2"HCl"_ ((aq)) -> "CaCl"_ (2(aq)) + "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#

Now, to get the complete ionic equation, use the fact that hydrochloric acid is a strong acid and that calcium chloride is soluble in water.

#"CaSO"_ (3(s)) + overbrace(2"H"_ ((aq))^(+) + 2"Cl"_ ((aq))^(-))^(color(blue)(=2"HCl"_ ((aq)))) -> overbrace("Ca"_ ((aq))^(2+) + 2"Cl"_ ((aq))^(-))^(color(blue)(" = CaCl"_ (2(aq)))) + "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#

To find the net ionic equation, eliminate the spectator ions, i.e. the ions that are present on both sides of the chemical equation

#"CaSO"_ (3(s)) + 2"H"_ ((aq))^(+) + color(red)(cancel(color(black)(2"Cl"_ ((aq))^(-)))) -> "Ca"_ ((aq))^(2+) + color(red)(cancel(color(black)(2"Cl"_ ((aq))^(-)))) + "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#

You will end up with

#"CaSO"_ (3(s)) + 2"H"_ ((aq))^(+) -> "Ca"_ ((aq))^(2+) + "SO"_ (2(g)) + "H"_ 2"O"_ ((l))#