Hydrogen chloride gas can be prepared by the following reaction:

Question

2NaCl(s) + H2SO4(aq) --> 2HCl(g) + Na2SO4(s)
How many grams of HCl can be prepared from 2.00 mol H2SO4 and 2.56 mol NaCl?

Answer 1

I have rewritten the equation without phases to save space. This is a limiting reagent (LR) problem and you know that because amounts are given for BOTH reactants.

2NaCl + H2SO4 --> 2HCl + Na2SO4

Usint 2.00 mols H2SO4 and all of the NaCl needed will give you 2.00 x (2 mols HCl/1 mol H2SO4) = 2.00 x 2 = 4.00 mol HCl

Using 2.56 mols NaCl and all of the H2SO4 needed will give you
2.56 x (2 mols HCl/2 mols NaCl) = 2.56 mols HCl.
Note the values are different (they usually are in LR problems) so one must be incorrect; the correct value in LR problems is ALWAYS the smaller value and the reagent producing that value is the LR. SO you will obtain 2.56 mol HCl.
Convert that value to grams. g = mols x molar mass = ?