# After looking at the schematics of the bubble, he finds that it holds 0.750 moles of gas at Standard Temperature and Pressure. Unfortunately for Rooster, helium gas is not sold by the mole, only by the liter. He needs to know how many liters of gas 0.750 moles of helium is.

16.8 L

Explanation:

From the question given above, the following data were obtained:

Number of mole of He = 0.750 mole

Volume of He =?

Recall:

1 mole of any gas occupy 22.4 L at STP. This also implies that 1 mole of He occupies 22.4 L at STP.

Finally, we shall determine the volume occupied by 0.750 mole of He. This can be obtained as follow:

1 mole of He occupied 22.4 L at STP.

Therefore, 0.750 mole of He will occupy = 0.750 × 22.4 = 16.8 L at STP.

Thus, 0.750 mole of He is equivalent to 16.8 L

Explanation:

Use the ideal gas equation:

Where:

p is the pressure: 202.6kPan is the number of moles: 0.050 molT is the temperatue in absolute scale: 400KR is the universal constant for ideal gases: 8.314 L-kPa / K-molV is the volumeSubstitute and solve for V:

Convert to liters:

The answer is rounded to two significant figures.

.217, .311, and .472, respectively.

Explanation:

The total number of moles of gas is 3.50 + 5.00 + 7.60 = 16.10 (to preserve significant digits).

X of helium=3.50/16.10 = .217

X of krypton=5.00/16.10 = .311

X of neon=7.60/16.10 = .472

1. Partial pressure of H₂ = 2 atm

2. Partial pressure of He = 2 atm

Explanation:

The following data were obtained from the question:

Mole of H₂ = 3.50 moles

Mole of He = 3.50 moles

Total pressure (Pₜ) = 4 atm

Partial pressure of H₂ =?

Partial pressure of He =?

Next, we shall determine the mole fraction of each gas this can be obtained as follow:

Mole of H₂ = 3.50 moles

Mole of He = 3.50 moles

Total mole = Mole of H₂ + Mole of He

Total mole = 3.50 + 3.50

Total mole = 7 moles

Mole fraction of H₂ = mole of H₂ / Total mole

Mole fraction of H₂ = 3.5/7

Mole fraction of H₂ = 0.5

Mole fraction of He = mole of He / Total mole

Mole fraction of He = 3.5/7

Mole fraction of He = 0.5

1. Determination of the partial pressure of H₂.

Mole fraction of H₂ = 0.5

Total pressure (Pₜ) = 4 atm

Partial pressure of H₂ =?

Partial pressure of H₂ = Mole fraction of H₂ × Pₜ

Partial pressure of H₂ = 0.5 × 4

Partial pressure of H₂ = 2 atm

2. Determination of the partial pressure of He.

Total pressure (Pₜ) = 4 atm

Partial pressure of H₂ = 2 atm

Partial pressure of He =?

Total pressure (Pₜ) = Partial pressure of H₂ + Partial pressure of He

4 = 2 + Partial pressure of He

Collect like terms

Partial pressure of He = 4 – 2

Partial pressure of He = 2 atm

Answer : The volume of the balloon after 45.0 hour is 128.5 L

Explanation :

First we have to calculate the moles of helium leaked.

In 1 hour, the number of moles of helium leaked = 10.0 mmol

In 45.0 hour, the number of moles of helium leaked =

conversion used : 1 mmol = 0.001 mole

Now we have to calculate the number of moles of helium remaining in the balloon.

Moles of helium remaining in the balloon = Total moles of helium - Moles of helium leaked

Moles of helium remaining in the balloon = 5.50 - 0.450 = 5.05 mole

Now we have to calculate the volume of the balloon after 45.0 hour.

According to the Avogadro's law, the volume of gas is directly proportional to the number of moles of gas at same pressure and temperature. That means,

or,

where,

= initial volume of gas = 140.0 L

= final volume of gas = ?

= initial moles of gas = 5.50 mole

= final moles of gas = 5.05 mole

Now we put all the given values in this formula, we get

Therefore, the volume of the balloon after 45.0 hour is 128.5 L