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2 years ago

1.) A balloon contains 0.126 mol of gas and has a volume of 2.74 L .

Chemistry

1 answer:

Ann [662]2 years ago

4 0

Answer:

<u></u>

<u>Problem 1: 5.44L</u>

<u>Problem 2: 479mL</u>

Explanation:

<h2>Problem 1. </h2>

n₁ = 0.126 mol
V₁ = 2.74 L
n₂ = 0.126mol + 0.124mol
V₂ = ?
Conditions: constant temperature and pressure

<u>b) Physical principles:</u>

The volume occupied by a gas, when the temperature and pressure remain unchanged, is proportional to the number of moles of gas.

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

<u>c) Solution:</u>

Solve for V₂ , substitute and compute:

$V_2=n_2\times\dfrac{V_1}{n_1}\\ \\\\ V_2=(0.126mol+0.124 mol)\times \dfrac{2.74L}{0.126mol}\\ \\ \\ V_2=5.44L$

<h2>Problem 2.</h2>

n₁ = 0.547mol
V₁ = 295 mL
V₂ = ?
n₂ = 0.547mol + 0.342 mol
Conditions: constant temperature and pressure

<u>b) Physical principles:</u>

The same as above: the volume occupied by a gas, when the temperature and pressure remain unchanged, is proportional to the number of moles of gas.

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

<u>c) Solution:</u>

Solve for V₂ , substitute and compute:

$V_2=n_2\times\dfrac{V_1}{n_1}\\ \\\\ V_2=(0.547mol+0.342 mol)\times \dfrac{295mL}{0.547mol}\\ \\ \\ V_2=479mL$

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