Question

1. a sample of chlorine gas kept in a 1.8 l container at 32.0 °c exerts a pressure of 4.0 atm. calculate the amount of moles of gas present. (record your answer in the numerical - response section below.)

Explanation:

Step1: Convert temperature to Kelvin

$T=(32.0 + 273.15)\text{ K}=305.15\text{ K}$

Step2: Use the ideal - gas law $PV = nRT$

We know $P = 4.0\text{ atm}$, $V=1.8\text{ L}$, $R = 0.0821\frac{\text{L}\cdot\text{atm}}{\text{mol}\cdot\text{K}}$, and $T = 305.15\text{ K}$. Rearranging the ideal - gas law for $n$ gives $n=\frac{PV}{RT}$.

Step3: Substitute values into the formula

$n=\frac{4.0\text{ atm}\times1.8\text{ L}}{0.0821\frac{\text{L}\cdot\text{atm}}{\text{mol}\cdot\text{K}}\times305.15\text{ K}}$
$n=\frac{7.2}{25.052815}\text{ mol}\approx0.29\text{ mol}$

Answer:

$0.29$