Question

1. As the temperature of the gas in a balloon decreases, which of the following occurs? The volume of the balloon increases. *** The average kinetic energy of the gas decreases. The gas pressure inside the balloon increases. all of the above 2. If a sealed syringe is heated, in which direction will the syringe plunger move? out in The plunger will not move. ******** The direction cannot be predicted. 3. If a balloon containing 3000 L of gas at 39°C and 99 kPa rises to an altitude where the pressure is 45.5 kPa and the temperature is 16° C, the volume of the balloon under these new conditions would be calculated using the following conversion factor ratios: ____.
Chemb.01.08.3a
Chemb.01.08.3b
Chemb.01.08.3c******
Chemb.01.08.3d


4. What happens to the partial pressure of oxygen in a sample of air if the temperature is increased?

It increases.
It stays the same.
It decreases.
The change cannot be determined. ******



5. A breathing mixture used by deep-sea divers contains helium, oxygen, and carbon dioxide. What is the partial pressure of oxygen at 101.4 kPa if PHe = 82.5 kPa andChemb.01.08.06= 0.4 kPa?



82.9 kPa******
19.3 kPa
18.5 kPa
101.0 kPa


6. Which of the following gases is the best choice for inflating a balloon that must remain inflated for a long period of time?

argon
oxygen
hydrogen *****
neon

Answer 1

The correct answers for the following six questions are these:
(1) The average kinetic energy of the gas decreases. Since average kinetic energy is the source of temperature.
(2) out
(3) Chemb.01.08.3c
(4) It increases. 
(5) 82.9 kPa
(6) argon

Answer 2

Answer 1:
Correct Answer: The average kinetic energy of the gas decreases.
Reason: 
From the ideal gas equation, we know that PV = nRT
where, P = pressure, V = volume, n = number of moles of gas, R = gas constant and T = temperature.

From above equation, it can be seen that, Temp. as a direct relation with Pressure and Volume. Hence, as temperature of the gas in a balloon decreases, pressure and volume also decreases. 

Also, from kinetic theory of gases, we know that, kinetic energy of gas increases with increasing temp. Hence,  average kinetic energy of the gas decreases with decreasing temp.  

Answer 2: 
Correct answer: Out
Reason: 
From the ideal gas equation, we know that PV = nRT
where, P = pressure, V = volume, n = number of moles of gas, R = gas constant and T = temperature.

Therefore, when a sealed syringe is heated, it's temp. will increase. This, will result in expansion of gas i.e volume will increase. Hence, syringe plunger move in outwards direction.

Answer 3: Volume = 6046 L
Reason: 
From the ideal gas equation, we know that PV = RT
where, P = pressure, V = volume, R = gas constant and T = temperature.
Given: P1 = 99 kPa, V1 = 3000 L, T1 = 312 K, P2 = 45.5 KPa and  T2 = 289 K.

Therefore, we have: $\frac{\text{P1 V1}}{\text{P2 V2}} = \frac{\text{R T1}}{\text{R T2}}$
Thus, $\frac{\text{99 3000}}{\text{45.5 V2}} = \frac{\text{R 312}}{\text{R 289}}$

Hence, V2 = 6046 L

Answer 4: 
Correct Answer: It increases
Reason: 
We know that, pressure of gas, it directly proportional to temp. Hence, when the temp. of as is increases. Total pressure of gas mixture increases. This is because, partial pressure of individual component (in present case oxygen) increases.

Answer 5: 
Correct answer: 18.5 kPa
Reason:
We know that, total pressure is the sum of the partial pressures of the gases present in it. Mathematically, it can be expressed as:

                           Ptot = PO2 + PHe + PCO2

Therefore,  partial pressure of oxygen, PO2:

                         PO2 = Ptot − PHe − PCO2

                                = 101.4 − 82.5 − 0.4

                                =18.5 kPa.

Answer 6: 

Correct Answer: Argon

Reason: 

Inert gases are the best choice for inflating a balloon that must remain inflated for a long period of time. Among given options, both neon and argon are inert gas, But, atomic weight of Ar is 40g/mol, while is more than that of neon (20 g/mol). Hence,. Argon gas is preferred over neon gas.