# Question 5018b

Apr 22, 2017

$\text{16.0 g}$

#### Explanation:

STP conditions are usually given as a pressure of $\text{1 atm}$ and a temperature of ${0}^{\circ} \text{C}$. Under these conditions, $1$ mole of any ideal gas occupies $\text{22.4 L}$ $\to$ this is known as the molar volume of a gas at STP.

Using the molar volume of a gas at STP, you can calculate the number of moles of oxygen gas present in your sample

11.2 color(red)(cancel(color(black)("L"))) * "1 mole O"_2/(22.4color(red)(cancel(color(black)("L")))) = "0.50 moles O"_2#

To convert this to grams, use the molar mass of oxygen gas

$0.50 \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{moles O"_2))) * "32.0 g"/(1color(red)(cancel(color(black)("mole O"_2)))) = color(darkgreen)(ul(color(black)("16.0 g}}}}$

The answer is rounded to three sig figs, the number of sig figs you have for the volume of oxygen gas.