# Question #fb120

Apr 20, 2017

The total mass of water is 18 g.

#### Explanation:

It you have two rooms of hydrogen, the hydrogen is in excess and oxygen is the limiting reactant.

The balanced equation is

$\text{2H"_2 + "O"_2 → "2H"_2"O}$

${\text{Moles of O"_2 = 16 color(red)(cancel(color(black)("g O"_2))) × ("32.00 g O"_2)/(1 color(red)(cancel(color(black)("mol O"_2)))) = "0.500 mol O}}_{2}$

$\text{Moles of H"_2"O" = 0.500 color(red)(cancel(color(black)("mol O"_2))) × ("2 mol H"_2"O")/(1 color(red)(cancel(color(black)("mol O"_2)))) = "1.00 mol H"_2"O}$

$\text{Mass of H"_2"O" = 1.00 color(red)(cancel(color(black)("mol H"_2"O"))) × (18.02 "g H"_2"O")/(1 color(red)(cancel(color(black)("mol H"_2"O")))) = "18 g H"_2"O}$