Question

A gas sample has 0.49 moles and occupies 1.20 L. How many moles of gas are added to increase the volume to 4.30 L?

Answer 1

1.76moles

Explanations:

The number of moles of gas "n" is directly proportional to its volume "v". This can be expressed as:

`\begin{gathered} n\alpha v \\ n=kv \\ k=(n_1)/(v_1)=(n_2)/(v_2) \end{gathered}`

where:

n1 and n2 are initial and final moles respectively

v1 and v2 are the initial and final volumes

Given the following parameters

`\begin{gathered} n_1=0.49mole \\ v_1=1.20L \\ v_2=4.30L \end{gathered}`

Required

Final number of moles "n2"

Substitute the given parameters into the formula

`\begin{gathered} n_2=(n_1v_2)/(v_1) \\ n_2=(0.49*4.30)/(1.20) \\ n_2=(2.107)/(1.20) \\ n_2=1.76moles \end{gathered}`

Hence the moles of gas added to increase the volume to 4.30L is 1.76moles