Combined Gas Laws
500.0 liters of a gas in a flexible-walled container are prepared at 700.0 mmHg and 200.0 °C. The gas is placed into a tank under high pressure. When the tank cools to 20.0 °C, the pressure of the gas is 30.0 atm. What is the volume of the gas?
9.51 L
If I have 6 moles of gas at 3.3 atm and 13 L, what would the T be? write your answer in 3 sig figs
87.2 K
Convert 338 L at 63.0 atm to its new volume at standard pressure.
21,294 L
What are the signs for heat and work for a gas that warms and, at the same time, is
expanded?
+q and -w
How do I calculate delta ∆V?
Vfinal - Vinitial
What is the volume of gas at 2.00 atm and 200.0 K if its original volume was 300.0 L at 0.250 atm and 400.0 K.
18.75 mL
If I have 3.7 moles of gas at 5 L and 210 K, what would the Pressure be? write your answer in 3 sig figs and atm.
12.8 atm
At 27.00 °C a gas has a volume of 6.00 L. What will the volume be at 150.0 °C?
8.46L
If the internal energy of a thermodynamic system is increased by 200 J while 50 J of
expansion work is done, how much heat was transferred, and in which direction, to or from
the system?
250 J transferred to the system
What is the conversion factor that can get us from units L*atm to J?
101.325 J/ 1 L*atm
If I start with 14 mL at 20.0 °C and 1.2 atm, and heat it to 41 °C while increasing the pressure to 2.2 atm, what would be the new volume? Write your answer in 3 sig figs.
8.18 mL
Determine the volume occupied by 2.34 grams of carbon dioxide gas at STP.
1.19 L
A 30.0 L sample of nitrogen inside a rigid, metal container at 20.0 °C is placed inside an oven whose temperature is 50.0 °C. The pressure inside the container at 20.0 °C was at 3.00 atm. What is the pressure of the nitrogen after its temperature is increased to 50.0 °C?
3.31atm
A sample of an ideal gas at 25.0 atm and 10.0 L is allowed to expand against a constant external pressure of 5.00 atm at constant temperature. Calculate the work in units of kJ for the gas expansion. (Hint: Boyles Law first, then find w)
-20.3 kJ
What are the equations we use to find ∆E and w? (2 separate equations)
∆E = q +w
w= (-Pext )(∆V)
A balloon of air now occupies 10.0 L at 25.0 °C and 1.00 atm. What temperature was it initially, if it occupied 9.40 L and was in a freezer with a pressure of 0.939 atm? Write your answer using 2 sig figs in °C.
-10 °C
If I have 0.7 moles of gas at 1.3 atm and 43 L, what would the T be? Write your answer in °C using 3 sig figs
700 °C
A mixture of gases with a pressure of 600.0 mmHg contains 70 percent nitrogen and 30 percent oxygen by volume What is the partial pressure of oxygen in this mixture? Write your answer in 2 sig figs
180 mmHg
A sample of an ideal gas is allowed to expand from an initial volume of 0.200 L to a final volume of 3.50 L against a constant external pressure of 0.995 atm. At the same time, 117 J of heat is transferred from the surroundings to the gas. What is the total change in the internal energy (ΔE) of the gas in joules?
−216 J
Which type of energy is the sum of a
substance’s kinetic and potential energies?
Internal Energy
At conditions of 785.0 torr of pressure and 15.0 °C temperature, a gas occupies a volume of 45.5 mL. What will be the volume of the same gas at 745.0 torr and 30.0 °C?
50.5 mL
5.600 g of solid CO2 is put in an empty sealed 4.00 L container at a temperature of 300 K. When all the solid CO2 becomes gas, what will be the pressure in the container?
0.783 atm
What volume (in L) will 5.5 g of oxygen gas occupy if 2.2 g of the oxygen gas occupies 3.0 L? (Under constant pressure and temperature.)
7.5 L
A sample of an ideal gas in the cylinder of an engine is compressed from 400 mL to 50.0 mL during the compression stroke against a constant pressure of 8.00 atm. At the same time, 140 J of energy is transferred from the gas to the surroundings as heat. What is the total change in the internal energy (ΔU) of the gas in joules?
144J
If I have a cup of water that feels really hot to the touch, what kind of reaction is taking place inside that cup? (exothermic or endothermic)
Endothermic! ( heat is being released from the cup to the surroundings)