Mole Mania Worksheet
1 Nate has 27.0g of krypton. How many moles of krypton does Nate have? T/I
n = ? m = 27.0 g M
Kr
= 83.80 g/mol
n = m/M = 27.0/83.80 = 0.322 mol
Nate has 0.322 mol of krypton.
2 Bonnie borrowed beryllium from behind the lab bench. If Bonnie has 1.23g of beryllium, how many beryllium
atoms does Bonnie have? T/I
n = ? m = 1.23 g M
Be
= 9.01 g/mol
n = m/M = 1.23/9.01 = 8.22 x 10 22 atoms
Bonnie has 8.22 x 10 22 atoms of beryllium.
3 Alexander held his breath until he was given 2.34x10
18 molecules of oxygen. How many moles of oxygen did
Alexander get? T/I
Divide particles by the number of particles in a mole (Avogadro’s number)
2.34 x 10 18 molecules/6.02 x 10 23 atoms/1mol = (2.34/6.02)(10
= 0.388 x 10 -5
= 3.88 x 10 -6 mol O
2
18-23 )
Alexander got 3.88 x 10 -6 moles of oxygen.
4 Alice secretly stashed silver sulphide in her knapsack. If Alice stashed 97.0g of silver sulphide, how many
moles of silver sulphide did Alice stash? K/U, T/I
n = ? m = 97.0 g M
Ag2S
= 2M
Ag
+ M s
M
Ag
= 107.87 g/mol M
= (2 x 107.87 g/mol) + 97.0 g/mol
= 215.74 + 32.07
= 247.8 g/mol s
= 97.0 g/mol
n = m/M
= 97.0/247.8
= 0.391 mol
Alice stashed 0.391 moles of silver sulphide.

5 Flora wants some tungsten. If Flora wants exactly 2.75 moles of tungsten, how many grams of tungsten
must Flora weigh out? T/I
n = 2.75 moles m = ? M
W
= 183.84 g/mol
n = m/M
m = n x M
= 2.75 x 183.84
= 505.56
= 505.6 g
Flora needs to weigh out 505.6g of tungsten.
6 Robert is in a pickle, he needs some acetic acid to pickle some pickles. Help Robert determine the molar
mass of acetic acid. T/I
formula for acetic acid = CH
3
COOH
M
C
= 12.01 g/mol M
H
= 1.01 g/ml M
O
= 16.00 g/mol
molar mass of acetic acid = 2M
C
+ 4 M
H
+ 2 M
O
= (2 x 12.01) + (4 x 1.01) + (2 x 16.00)
= 24.02 + 4.04 + 32.00
= 60.06
= 60.1 g/mol
The molar mass of acetic acid is 60.1 g/mol
7 Lucy needs a pinch of sodium hydrogen carbonate for her baking. Help Lucy determine the molar mass of
sodium hydrogen carbonate. T/I
formula for sodium hydrogen carbonate = NaHCO
3
M
Na
= 22.99 g/mol M
H
= 1.01 g/ml M
C
= 12.01 g/mol M
O
= 16.00 g/mol
molar mass of sodium hydrogen carbonate = M
Na
+ M
H
+ M
C
+ 3 M
O
= 22.99 + 1.01 + 12.01 + (3 x 16.00)
= 36.01 + 48.00
= 84.01
= 84.0 g/mol
The molar mass of sodium hydrogen carbonate is 84.0 g/mol.

8a Aaron put potassium permanganate in a container that can hold 7.50 x10 22 atoms. (Tricky ) How many moles of
potassium permanganate are in the container? T/I
formula for potassium permanganate = KMnO
4
K = 1 x 6.02 x 10 23 atoms = 6.02 x 10 23 atoms
Mn = 1 x 6.02 x 10 23 atoms = 6.02 x 10 23 atoms
O = 4 x 6.02 x 10 23 atoms = 24.08 x 10 23
36.12 x 10
atoms
23 atoms/mole
Divide total atoms by the number of atoms in a mole
7.50 x10 22 atoms / 36.12 x 10 23 = 7.5 x 36.12 x 10 22-23
= 0.20764 x 10 -1
= 0.0208 moles
There are 0.0208 moles of potassium permanganate in the container.
b Aaron’s friend Adrian marveled at Aaron’s potassium permanganate pile. Adrian deviously dared Aaron to calculate the true mass of the pile. The one who calculates the correct answer first gets to keep the pile.
Help Aaron keep his precious potassium permanganate pile by helping him determine the mass.
T/I
formula for potassium permanganate = KMnO
4
M
K
= 39.10 g/mol M
Mn
= 54.94 g/mol M
O
= 16.00 g/mol
M
KMnO4
= M
K
+ M
Mn
+ 4 M
O
= 39.10 + 54.94 + (4 x 16.00)
= 94.04 + 64.00
= 158.04
= 158.0 g/mol
The molar mass of the potassium permanganate is 158.0 g/mol.
n = 0.0208 mol (from question 8a) M
KMnO4
= 158.0 g/mol m = ?
n = m/M
m = n x M
= 0.0208 x 158.0
= 3.2864
= 3.29 g
The mass of the potassium permanganate is 3.29 g.

9. Roohie made Juliana mark “moles of chlorine gas” on a container. Roohie carefully calculated chlorine’s mass
to be 2.35 g. How many moles of chlorine are crammed in the container? T/I n = ? m = 2.35g M
Cl2
= 35.45 g/mol x 2 = 70.9 g/mol n = m/M = 2.35/70.9
= 0.0331 mol
There are 0.0331 moles of chlorine in the container.
Assessment :
All questions are Thinking/Investigation
T/I
Questions 1-3, 5 and 9 are worth 2 marks each
Questions 4, 6-8 are worth 3 marks each
This problem set could be used as Assessment for learning to determine whether students understand concept of the mole and then used to decide how to differentiate instruction based on results OR it could be used as
Assessment as Learning since answers are given (lucky for me!) and students can gauge what they need additional practice or help with OR it could be used as Assessment for Learning (without the answers of course).
After thinking about it, I think this problem set would be best as Assessment as Learning.