As an acid sulphur dioxide reacts with sodium hydroxide solution to form a salt called sodium sulphate Na2SO3 and water. Write a balanced chemical equation for the reaction (show state symbols)?

1 Answer
Apr 13, 2018

SO2(g)+2NaOH(s)Na2SO3(s)+H2O(l)

Explanation:

SO2+NaOHNa2SO3+H2O

Now, a balanced equation of a reaction has equal atoms of each element on both sides. So we count the atoms each element.

  • We have 1 atom of Sulphur on the one side (SO2) and 1 on the other side (Na2SO3).

  • We have 3 atoms of Oxygen on the one side (SO2 and NaOH), but 4 on the other side (Na2SO3 and H2O).

  • We have 1 atom of Sodium (NaOH), but 2 on the other side (Na2SO3).

  • We have 1 atom of Hydrogen (NaOH), but 2 on the other side (H2O).

So to balance it:

SO2(g)+2NaOH(s)Na2SO3(s)+H2O(l)

SO2 is a gas.
NaOH is a powder, which means its solid.
Na2SO3 is a salt in the form of a powder, which is solid.
H2O is liquid, for obvious reasons.