Mole Calculations Again Homework
I.
Calculate the following, assuming all are at STP.
1.
What is the volume of 9.6 mole helium?
9.6 mole He
2.
What is the volume of 3.2 mole carbon monoxide?
3.2 mole CO
3.
1 mol N2O
22.4 L N2O
How many moles of oxygen are in 0.350 L of oxygen?
0.350 L O2
5.
22.4 L
1 mole CO
How many moles of dinitrogen monoxide are in 56.0 L of dinitrogen monoxide?
56.0 L N2O
4.
22.4 L
1 mole He
1 mol O2
22.4 L O2
What is the volume of 3.24 x 1022 molecules of any gas?
3.24 x 1022 molecules
6.
What is the mass of 18.0 L of methane, CH4?
18.0 L CH4
7.
1 mol CH4
22.4 L CH4
16.9 g CH4
1 mol CH4
What is the volume of 835 g of sulfur trioxide?
835 g SO3
8.
1 mol
22.4 L
23
6.022 x 10 molecules 1 mol
1 mol SO3
80.0 g SO3
22.4 L SO3
1 mol SO3
How many molecules are in 25.0 L of carbon dioxde?
25.0 L CO2
1 mol CO2
22.4 L CO2
6.022 X 1023 mc CO2
1 mol CO2
9.
How many molecules are in 3.25 L of nitrogen monoxide?
3.25 L NO
10.
6.022 X 1023 mc NO
1 mol NO
1 mol NO
22.4 L NO
How many hydrogen atoms are in 50.0 L of hydrogen gas (H2)?
50.0 L H2
1 mol H2
22.4 L H2
6.022 X 1023 mc H2
1 mol H2
2 atoms H
1 mc H2
II. Determine what units are given and what units are asked for in each problem. This will tell you what
conversion factors you will need to use in each problem.
You may need these conversions
1 mole = 6.02 x 1023 particles (atoms, molecules, form. units)
For the following problems:
1 mole = 22.4 L (gas at STP)
1 mole = formula mass (in grams) of a substance
11.
What is the mass of 0.250 moles of ammonium cyanide?
0.250 mol NH4CN
12.
How many moles are in 35.0 g of sodium sulfate?
35.0 g Na2SO4
13.
1 mol N2
22.4 L N2
How many molecules are present in 2.50 moles of carbon disulfide?
2.50 mol CS2
16.
22.4 L CO2
1 mol CO2
How many moles are present in 35.0 L of nitrogen gas at STP?
35.0 L N2
15.
1 mol Na2SO4
142 g Na2SO4
What is the volume (in L) of 0.375 moles of carbon dioxide gas at STP?
0.375 mol CO2
14.
44.0 g NH4CN
1 mol NH4CN
6.022 X 1023 mc CS2
1 mol CS2
How many moles are present in 4.50 x 10 24 formula units of potassium nitrate?
4.50 X 1024 fu KNO3
17.
1 mol KNO3
6.022 X 1023 fu KNO3
What is the mass of 45.0 L of sulfur trioxide gas?
45.0 L SO3
1 mol SO3
22.4 L SO3
80.0 g SO3
1 mol SO3
18.
What is the volume (in L) of 28.0 g of dinitrogen monoxide gas?
28.0 g N2O
19.
1 mol N2O
44.0 g N2O
What is the mass of 6.58 x 1022 formulas units of barium carbonate?
6.58X 1022 fu BaCO3
20.
1 mol PCl3
136 g PCl3
1 mol CO
28.0 g CO
6.022 X 1023 mc CO 1 mol CO
How many molecules are present in 54.0 L of fluorine gas at STP?
54.0 L F2
23.
6.022 X 1023 mc PCl3
1 mol PCl3
What is the volume (in L at STP) of 4.50 x 1021 molecules of carbon monoxide?
4.50 X 1021 mc CO
22.
1 mol BaCO3
198 g BaCO3
23
6.022X 10 fu BaCO3 1 mol BaCO3
How many molecules are present in 75.0 g of phosphorus trichloride?
75.0 g PCl3
21.
22.4 L N2O
1mol N2O
1 mol F2
22.4 L F2
6.022 X 10 23 mc F2
1 mol F2
What is the formula mass of a gas that has a density of 6.50 g/L at STP?
DXV=M
(6.50 g/L) (22.4 L/mol) = M
24.
What is the density of nitrogen trifluoride gas at STP?
D
=
M
V
D
=
71.0 g/mol
22.4 L/mol