2.
● You have 3.11 x 10^22 molecules of tetraphosphorous decoxide. What mass, in grams, is this sample? Final answer must have correct sig figs; do not list any units.
● You have a sample of 5.08 x 10^22 formula units of barium phosphate. What mass, in grams, do you have? Final answer must have correct sig figs; do not list any units.
● You have a 50. gram sample of aspirin, C9H8O4. How moles of CARBON do you have in this sample? Final answer must have correct sig figs; do not list any units.
# 6.
● A 5.3 liter helium balloon has a gas temperature of 28 degrees Celsius and a gas pressure of 735 mm Hg. What is the new pressure, in mm Hg, if the temperature rises to 86 degrees Celsius and the volume decreases to 4.7 liters?
● A bag of cheetos contains 585 mL of air. The air inside the bag is 25 degrees Celsius and has a pressure of 765 mm Hg. You drive to a peak in the Sierra Nevada mountains where the pressure is 442 mm Hg and a temperature of 5 degrees Celsius. What will be the new volume of the cheetos bag? Express you volume in mL with three sig figs.
● A sample of a gas has an initial volume of 62.3 L at a pressure of 1.6 atm. If the sample is compressed to a volume of 18.3 L, what happens to the pressure of the gas?
○ Group of answer choices
○ pressure increases
○ pressure decreases
○ pressure stays the same
○ depends on the identity of the gas
● A particular sample of gas has its pressure tripled and its Kelvin temperature tripled. How does the volume change?
○ Group of answer choices
○ volume stays the same
○ volume is increased by 3
○ volume is reduced by ⅓
○ volume is doubled
A sample of a gas has an initial volume of 62.3 L at a temperature of 310 K. If the temperature of the gas sample is increased to 380 K, what happens to the volume?
● Group of answer choices
○ volume increases
○ volume decreases
○ volume stays the same
○ depends on the identity of the gas
● You have 4 rigid containers; each container has a volume of 5.0 L. Each container holds 10.00 grams of a different gas: He(g), Ne(g), Ar(g), Kr(g). The container with which gas has the greatest pressure inside?
● You have four balloons; each balloon contains 20.00 grams of the following gases: H2(g), He(g), N2(g) and O2(g). Which balloon has the largest volume?
# 7.
● You have 5.62 liters of hydrogen gas at STP. How many grams of hydrogen gas do you have?
● What is the temperature of 0.52 mol of a gas at a pressure of 1.3 atm and a volume of 11.8 L? Express your final answer in degrees Celsius with two sig figs.
● A small mass of liquid oxygen (0.116 g) is sealed into a flexible balloon. The liquid oxygen vaporizes into gaseous oxygen. The balloon inflates to 92.0 mL and the gas has a temperature of 25 deg Celsius. What is pressure of the oxygen in the balloon? Your final answer should have 3 sig figs....do not round sig figs in intermediate steps!
● A helium balloon has a volume of 2.5 L, a pressure of 955 mm Hg and a gas temperature of 305 K. What would be the volume, in L, of this helium balloon at STP? Your final answer should have 2 sig figs...do not round sig figs in intermediate steps!
● A sample of nitrogen gas in an airbag has a pressure of 1.20 atm, a temperature of 15 deg Celsius and a volume of 798 mL. What mass, in grams, of nitrogen gas is present in the airbag? Your final answer should have 3 sig figs....do not round sig figs in intermediate steps!
#8
● Sodium reacts with nitrogen gas according to the following reaction:
6Na(s) + N2(g) --> 2Na3N(s)
How many grams of sodium are required to completely react with 115 mL of nitrogen gas at STP?
● Consider the following balanced chemical equation:
N2(g) + 3H2(g) --> 2NH3(g)
If you react 14.0 grams of nitrogen gas with 2.50 grams of hydrogen gas, what pressure of ammonia (NH3) gas could you collect in a 10.0 liter flask at temperature of 25 deg Celsius?
● Evaluate the propane combustion reaction (it's unbalanced!):
___C3H8(g) + ___O2(g) --> ___CO2(g) + ___H2O(g)
This reaction occurs in a 250. mL combustion chamber of an engine. It is determined an amount of carbon dioxide gas is produced in this chamber at a pressure of 1255 mm Hg and a temperature of 42 deg Celsius. What volume (in mL) of propane must have been injected into this chamber at STP conditions?

2. ● You have 3.11 x 10^22 molecules of tetraphosphorous decoxide....