Question

If ten volumes of dihydrogen gas reacts with five volumes of dioxygen gas, how many volumes of water vapor would be produced?

Answer 1

Dihydrogen gas reacts with dioxygen gas as,
2H 2 (g) + O 2 (g) → 2H 2 O(g)
Thus, two volumes of dihydrogen react with one volume of dihydrogen to produce two volumes of water vapour. Hence, ten volumes of dihydrogen will react with five volumes of dioxygen to produce ten volumes of water vapour.

Answer 2

"Dihydrogen" reacts with "dioxygen" to form water. The reaction is as follows,

$6{ H }_{ 2 }\quad +\quad 3{ O }_{ 2 }\quad =\quad 6{ H }_{ 2 }O$

Now, 6 volumes of dihydrogen react with 3 volume of dihydrogen to produce 6 volumes of ""water vapour"".

Hence, "ten volumes" of "dihydrogen" will react with "five volumes" of "dioxygen" to produce "ten volumes"" of "water vapour"."