# The pressure in a 5.75 L container of 48.0 g of bromine gas at 100.0°C is ....... What is the pressure in atm?

Mar 28, 2015

Alright, so we want to use the ideal gas law to solve for Pressure.

$P V = n R T$

Pressure is unknown
Volume is 5.75 L
n is the number of mols, which we must solve for
R is the gas constant, 0.082
T is the temperature in K, which we must solve for

Solving for n: As you may recall, the formula for moles is $n = \frac{m a s s}{m o l a r m a s s}$. We know that the mass is 48.0 grams, and that the Molar Mass of Br is 79.90. However, Br is diatomic (it's formula is $B {r}_{2}$), therefore we must multiply the molar mass by 2, to get 159.8.

Using this, we solve that n=0.300

Solving for T in K: We are given that the temperature is 100.0ºC. The formula for converting ºC-->K is: ºC+273.15=K

Therefore, the temperature is 373.2 K

Now, we can plug this all into the Ideal Gas Law to solve for Pressure in atm

$P \left(5.75\right) = \left(0.300\right) \left(.082\right) \left(373.2\right)$
$P = \frac{\left(0.300\right) \left(.082\right) \left(373.2\right)}{5.75}$
$P = 1.60 a t m$