# How many grams of oxygen gas present in a 2.50-L sample kept at 1.66 atm pressure and a temperature of 10.0°C?

May 26, 2016

Approx. $0.2 \cdot m o l$
We use the Ideal Gas equation: $P V = n R T$, and the appropriate gas constant $R$.
$n$ $=$ $\frac{P V}{R T}$ $=$ $\frac{1.66 \cdot a t m \times 2.50 \cdot L}{0.0821 \cdot L \cdot a t m \cdot {K}^{-} 1 \cdot m o {l}^{-} 1 \times 283 \cdot K}$
$\cong$ $0.20 \cdot m o l$