2H2 + 02 -> 2H2O.

Alright. Next, you use dimensional analysis.

2 mol H2(2 mol H2O/2 mol H2)(18.01g H2O/1 mol H2O)…

so you have 2 * 2 * 18.01, divided by 2. Which is about 36.02g H2O.

For the NaCl, you must once again write a balanced equation.

2Na + Cl2 -> 2NaCl

Then you use dimensional analysis.

6 mol Na(2 mol NaCl/2 mol Na)(57.44g NaCl/1 mol NaCl)…

which is 6*2*57.44 divided by 2…which is about 344.64g NaCl.

2H2 + O2 —> 2H2O

Then, use stochiometry…

2 moles of H2 x (2 moles of H2O / 2 moles H2) = 2 moles of H20.

You must convert that to grams using the molar mass of H20 (add the molar masses of each atom together)…

1.008 + 1.008 + 16 = 12.016 grams

2 moles x (12.016 grams / 1 mole) = 24.32 grams

2. Set up the equation again…

Na + Cl —> NaCl

Stochiometry…

6 moles of Na x (1 mole of Na / 1 mole of Cl) = 6 moles of NaCl.

Get molar mass…

22.99 + 35.453 = 58.443 grams

And convert…

6 moles of NaCl x (58.443 grams / 1 mole) = 350.658 grams