Question

Part A

A balloon is floating around outside your window. The temperature outside is 33 ∘C , and the air pressure is 0.800 atm . Your neighbor, who released the balloon, tells you that he filled it with 3.90 moles of gas. What is the volume of gas inside this balloon?

Express your answer to three significant figures and include the appropriate units.

Part B

A 20.0 L gas cylinder is filled with 6.60 moles of gas. The tank is stored at 45 ∘C . What is the pressure in the tank?

Express your answer to three significant figures and include the appropriate units.

Part C

A 220. L kiln is used for vitrifying ceramics. It is currently operating at 805 ∘C , and the pressure is 0.9750 atm . How many moles of air molecules are within the confines of the kiln?

Express your answer to three significant figures and include the appropriate units.

Part D

A 10.0 L gas cylinder has been filled with 4.40 moles of gas. You measure the pressure to be 4.20 atm . What is the temperature inside the tank?

Express your answer to three significant figures and include the appropriate units.

Answer 1

A)

Given:

P = 0.8 atm

n = 3.90 mol

T = 33.0 oC

= (33.0+273) K

= 306 K

use:

P * V = n*R*T

0.8 atm * V = 3.9 mol* 0.08206 atm.L/mol.K * 306 K

V = 122 L

Answer: 122 L

B)

Given:

V = 20.0 L

n = 6.60 mol

T = 45.0 oC

= (45.0+273) K

= 318 K

use:

P * V = n*R*T

P * 20 L = 6.6 mol* 0.08206 atm.L/mol.K * 318 K

P = 8.61 atm

Answer: 8.61 atm

C)

Given:

P = 0.975 atm

V = 220.0 L

T = 805.0 oC

= (805.0+273) K

= 1078 K

find number of moles using:

P * V = n*R*T

0.975 atm * 220 L = n * 0.08206 atm.L/mol.K * 1078 K

n = 2.425 mol

Answer: 2.43 mol

D)

Given:

P = 4.2 atm

V = 10.0 L

n = 4.40 mol

use:

P * V = n*R*T

4.2 atm * 10 L = 4.4 mol* 0.08206 atm.L/mol.K * T

T = 116 K

= (116-273) oC

= -157 oC

Answer: -157 oC