Homework Question H.5 (c)

[Anokhi Patel 2B]

Can someone help me balance this chemical equation:

NaCl(aq) + SO3(g) + H2O(l) -------> Na2SO4(aq) + HCl(aq)

I tried multiple approaches, but I can never get the oxygen to equal out.

Thank you.

[Juliet Stephenson 4E]

Hi Anokhi,
This is what worked for me:
We start with NaCl + SO3 + H2O --> Na2SO4 + HCl. Hydrogen and Sodium are unbalanced. Oxygen is already balanced because it has three moles from SO3 and 1 mole from H2O, which corresponds to the 4 moles of Oxygen in Na2SO4. To balance Hydrogen and Sodium, I'll add stoichiometric coefficient to NaCl in the reactants and HCl in the products.
2NaCl + SO3 + H2O --> Na2SO4 + 2HCl.

If we test this we find:
Reactants Products
2 moles Na 2 moles Na
2 moles Cl 2 moles Cl
1 mole S 1 mole S
4 moles O 4 moles S
2 moles H 2 moles H

[605136321]

a useful tool to help check if you're correct is:

http://www.endmemo.com/chem/balancer.php