PRACTICE PROBLEMS (GTF 101): CALCULATION FOR GASES

 Please use R = 0.0821 l. atm/mol.K; 0^oC = 273.15 K

Q1:  If 4L of H₂ gas at 1.43 atm is at constant temperature and the pressure was to increase by a factor of 2/3, what is the final volume of the H₂ gas?  (Hint: Boyle's Law)
Answer: 2.39 L

Q2:  If 1.25L of gas exists at 35^oC with a constant pressure of .70 atm in a cylindrical block and the volume were to be multiplied by a factor of 3/5, what is the new temperature of the gas?  (Hint: Charles's Law)
Answer:  184.89 K 

Q3: At 655 mm Hg and 25.0^oC, a sample of Chlorine gas has volume of 750mL.  How many moles of Chlorine gas at this condition?
Answer:  0.0263 moles

Q4:  5.0 g of neon is at 256 mm Hg and at a temperature of 35º C.  What is the volume?
Answer:  18.63 L 

Q5:  Find the volume, in mL, when 7.00 g of O2 and 1.50 g of Cl2 are mixed in a container with a pressure of 482 atm and at a temperature of 22º C.
Answer:  12 mL

Q6:  A 3.00 L container is filled with Ne (g) at 770mmHg at 27^oC.  A 0.633g sample of CO₂ vapor is then added.  What is the partial pressure of CO₂ and Ne in atm?  What is the total pressure in the container in atm?
Answers:  PCO2 = 0.118 atm; Ptotal = 1.20 atm

Q7:  What is the density of nitrogen gas (N₂) at 248.0 Torr and 18º C?  
Answer:  0.382 g/dL