Two evacuated bulbs of equal volume are connected by a tube of negligible volume. One of the bulbs is placed in a constant-temperature bath at 245 K and the other bulb is placed in a constant-temperature bath at 350 K . Exactly 5 mol of an ideal gas is injected into the system. Calculate the final number of moles of gas in each bulb.

Respuesta :

Answer:

The final number of moles of gas in each bulb is 2.06 and 2.94 moles.

Explanation:

The number of moles can be calculated using Ideal Gas Law:

[tex] PV = nRT [/tex]     (1)

Where:

P: is the pressure

V: is the volume

n: is the number of moles

R: is the ideal gas constant  

Solving equation (1) for n:

[tex] n = \frac{PV}{RT} [/tex]

For bulb 1 we have:

[tex] n_{1} = \frac{P_{1}V_{1}}{RT_{1}} [/tex]

and for bulb 2:

[tex] n_{2} = \frac{P_{2}V_{2}}{RT_{2}} [/tex]

Dividing n₁ by n₂:

[tex] \frac{n_{1}}{n_{2}} = \frac{\frac{P_{1}V_{1}}{RT_{1}}}{\frac{P_{2}V_{2}}{RT_{2}}} [/tex]

Since V₁ = V₂ and P₁ = P₂ we have:

[tex] \frac{n_{1}}{n_{2}} = \frac{\frac{P_{1}V_{1}}{RT_{1}}}{\frac{P_{2}V_{2}}{RT_{2}}} [/tex]

[tex] \frac{n_{1}}{n_{2}} = \frac{T_{2}}{T_{1}} = \frac{350}{245} = 1.43 [/tex]                

[tex] n_{1} = 1.43n_{2} [/tex]   (2)

Also, we have that 5 mol of an ideal gas is injected into the system:

[tex] n_{1} + n_{2} = 5 \rightarrow n_{1} = 5 - n_{2} [/tex]    (3)

By entering equation (3) into (2) we have:

[tex] 5 - n_{2} = 1.43n_{2} [/tex]

[tex] n_{2} = 2.06 [/tex]    (4)

(4) into (3):

[tex] n_{1} = 5 - n_{2} = 5 - 2.06 = 2.94 [/tex]      

Therefore, the final number of moles of gas in each bulb is 2.06 and 2.94 moles.

I hope it helps you!