Question

a large balloon expands from 4.5 l to 9.0 l when additional he is added. the balloon originally held 0.30 mol of he. the temperature and pressure remain constant. how many moles of he are in the expanded balloon? n₂ = ? mol

Explanation:

Step1: Apply Avogadro's Law

$\frac{V_1}{n_1} = \frac{V_2}{n_2}$ (T, P constant)

Step2: Rearrange for $n_2$

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

Step3: Substitute values

$n_2 = 0.30\ \text{mol} \times \frac{9.0\ \text{L}}{4.5\ \text{L}} = 0.60\ \text{mol}$

Answer:

0.60