Question

Question #a1fd3

Answer 1

`"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))`