# What pressure in Pascals will be exerted by 4.78 grams of oxygen gas in a 2.5-liter container at 20 C?

May 14, 2017

$P \cong 150 \cdot k P a$

#### Explanation:

From the Ideal Gas equation..........

$P = \frac{n R T}{V} = \frac{\frac{4.78 \cdot g}{32.00 \cdot g \cdot m o {l}^{-} 1} \times 0.0821 \cdot \frac{L \cdot a t m}{K \cdot m o l} \times 293 \cdot K}{2.50 \cdot L}$

$= 1.44 \cdot a t m \equiv 1.44 \cdot a t m \times 101.3 \cdot k P a \cdot a t {m}^{-} 1 = 145.6 \cdot k P a$

Note that you SIMPLY MUST KNOW that ${H}_{2} , {O}_{2} , {N}_{2} , {F}_{2} , C {l}_{2}$ are binuclear as the elements. In fact all the elemental gases (at RT) EXCEPT for the Noble Gases are bimolecular.