Question

What volume of `HCl(g)` will result from the reaction of `50*L` `H_2`, and `50*L` `Cl_2`?

Answer 1

Look at your stoichiometric equation....

`1/2H_2(g) + 1/2Cl_2(g) stackrel"catalysis"rarr HCl(g)`

Explanation:

And the equation EXPLICITLY states that one equiv of dihydrogen reacts with the one equiv of dichlorine to give TWO equiv of hydrogen chloride gas.

And so if we gots a `50*L` volume of `Cl_2`, we need a `50*L` volume of `H_2`, to give an `100*L` volume of `HCl`. And all I am doing is noting the stoichometry of the balanced equation...and relating this to the known gas laws....specifically the Avogadro condition: equal volumes of gas contain equal NUMBERS of molecules, given equivalent pressure and temperature.