Question

a balloon contains 0.950 of nitrogen gas at a volume of 25.5 L. How many grams of N2 should be released from the balloon to bring the volume to 17.3 L? ____g N2

Answer 1

Answer:

4.27 g

Explanation:

We can write that for a gas kept at constant pressure and temperature, the number of moles of the gas is directly proportional to its volume:

$n\propto V$

Which can be rewritten as

$\frac{n_1}{V_1}=\frac{n_2}{V_2}$

where here we have:

$n_1=0.950 mol$ is the initial number of moles

$V_1=25.5 L$ is the initial volume of the gas

$V_2=17.3 L$ is the final volume of the gas

So the final number of moles is

$n_2=\frac{n_1 V_2}{V_1}=\frac{(0.950)(17.3)}{25.5}=0.645 mol$

So the number of moles that should be released from the balloon is:

$\Delta n = n_1-n_2=0.950-0.645=0.305 mol$

The molar mass of gas N2 is

$M=14 g/mol$

Therefore, the mass of gas that should be released is:

$\Delta m = M\Delta n =(14.0)(0.305)=4.27 g$