AP Ch 5 review

In which flask do the molecules have the highest average velocity?

• NH₃

• CH₄

• O₂

• They are all the same

2.50 moles of N₂ is placed in a closed 3.00 L container at 25°C. If the temperature in the container is raised to 120°C, what will be the change in pressure?

• 26.9 atm

• 20.4 atm

• 12.0 atm

• 6.5 atm

Tags

NGSS.HS-PS3-4

0.278 moles of O₂ take up 2.37L. What is the density of O₂?

• 6.54 g/L

• 21.1 g/L

• 0.233 g/L

• 3.76 g/L

Which flask contains the greatest number of molecules?

• NH₃

• CH₄

• O₂

• All are the same

325 mL of a gas at STP has a mass of .805 grams. What is the molar mass of the gaseous compound?

• 31.7 g/mol

• 0.0555 g/mol

• 55.5 g/mol

• 9.04 g/mol

How many moles of gas would it take to fill an average man's lungs, total capacity of which is about 4.5 liters? Assume 1.00 atm pressure and 37.0°C.

• 0.18

• 1.24

• 0.75

• 11.2

What volume of O2 gas at STP would you need to have to get the same number of O₂ molecules as there are H₂ molecules in 25.0 L at 0.850 atm and 35°C?

• 32.3

• 4.2

• 18.8

• 0.656

An unknown gas ("A") effuses at 1.25 times the rate of carbon dioxide at identical conditions of pressure and temperature. What is the molar mass of gas "A"?

• 28.2 g/mol

• 35.2 g/mol

• 14.0 g/mol

• 64 g/mol

A 268 cm³ sample of gas at 18°C and 748 Torr is placed in a rigid container of volume 648cm³. To what °C must the assembly be heated so that the gas will fill the whole container at 748 Torr?

• 597°C

• 704°C

• 431°C

• 324°C

An 8.25 L sample of oxygen is collected at 25°C and 1.022 atm pressure. What volume will the gas occupy 0.940 atm and -15°C?

• 8.76

• 10.4

• 7.77

• 1.78