# The reaction between H_2 and O_2 produces 13.1 g of water. How many grams of O_2 reacted? 2H_2(g) + O_2(g) -> 2H_2O(g)?

Nov 20, 2016

Approx. $12 \cdot g$ of dioxygen gas.

#### Explanation:

There are $\frac{13.1 \cdot g}{18.01 \cdot g \cdot m o {l}^{-} 1} = 0.727 \cdot m o l$ of water product.

${H}_{2} \left(g\right) + \frac{1}{2} {O}_{2} \left(g\right) \rightarrow {H}_{2} O \left(l\right)$

Given the stoichiometry of the reaction, there were necessarily $0.727 \cdot m o l$ dihydrogen reactant, and $\frac{0.727 \cdot m o l}{2}$ dioxygen reactant. I speak of dihydrogen, dioxygen etc. because I wish to avoid the confusion of mistaking atoms for molecules and vice versa.

"Mass of dioxygen reactant "=(0.727*mol)/2xx32.00*g*mol^-1=??g