Question

If `12*L` of hydrogen gas react with `12*L` of chlorine gas, what volume of `HCl(g)` will result?

Answer 1

The volume of a gas is equivalent to the number of molecules it contains under equivalent temperature and pressure. And thus we should get `22.4*L` `HCl(g)`.

Explanation:

We interrogate the reaction:

`1/2H_2(g) + 1/2Cl_2(g) rarr HCl(g)`,

equivalently,

`H_2(g) + Cl_2(g) rarr 2HCl(g)`,

Given the opening statement, i.e. which is due to Avogadro, the volumes are proportional to the number of molecules each gas contains. Dihydrogen gas is present in HALF MOLAR proportion, and dichlorine is present in excess. And thus, given complete reaction, `11.2*L` of `H_2` reacts with `11.2*L` of `Cl_2` to give `22.4*L` `HCl(g)`.

All of this is based on the stoichiometric equation..........