Moles Quiz

I say atom, you say amu

What are you made of?

Need a mole? Just call 602-

1023

How big is that piece of pie?

Is it Really that easy?

1 1 1 1 1

2 2 2 2 2

3 3 3 3 3

4 4 4 4 4

5 5 5 5 5

Calculate the mass (amu) of a sample that contains 23 nitrogen atoms.

322.2 amu

Calculate the number of oxygen atoms in a sample that has a mass of 288 amu.

18.0 atoms

Calculate the mass (in amu) of a sample of Bromine that has the same number of atoms as a 343 amu sample of Calcium.

684 amu

Calculate the number of atoms in a 5.321 amu sample of molybdenum.

5.546 x 10-2 atoms

How many grams is 1 amu?

1.66 x 10-24 g

What is the percent composition of the elements found in carbon tetrafluoride?

13.65% C and 86.35%F

What is the percent composition of the elements in CuCl2?

47.27%Cu and 52.73% Cl

What is the mass percent of chlorinein sodium chloride?

39.34%Na and 60.66% Cl

What is the mass percent of the anion in calcium hydroxide?

45.91%

The percentage of sulfur in sulfur dioxideis about 50%. What is the percentageof oxygen in this compound?

About 50%

Calculate both the number of moles and the mass of a sample of chromium containing 5.00x1020 atoms.

8.30 x 10-4 mol and 4.32 x 10-2 grams

Calculate the number of moles in a 57.7 gsample of sulfur.

1.80 mol

Which weighs more, 0.50 mol of oxygen or 4 mol of hydrogen atoms?

.50 mol of Oxygen

Calculate the number of grams of iron that contains the same number of atoms as 2.24 g of cobalt.

2.12 g Fe

How many atoms are present in a 3.57 kg sample of aluminum?

7.97x1025 atoms

A single molecule of a particular compound has a mass of 4.65x10-23g. Which of the following could be this compound?

A.NO2

B.COC.WaterD.Ammonia

B.

What is the percent by mass of carbon in table sugar, C12H22O11

42%

Calculate the molar mass for magnesium sulfate.

120.38 g

Calculate the number of units of teflon (C2H4) in 135g.

2.90 x 1024

Compute the mass percent of each element in the formula for penicillin F (C14H2ON2SO4)

C 53.81%

H 6.453%

N 8.969%

S 10.27%

O 20.49%

A particular compound in the chemistry lab is found to contain 7.2x1024 atoms of oxygen, 56.0g of Nitrogen, and 4.0 mol of hydrogen. What is this compound’s empirical formula?

HNO3

What is the empirical formula of a compound that is 31.9% potassium, 28.9% chlorine, and 39.2% oxygen?

KClO3

A compound contains 259.2 grams of F and40.8 grams of C. What is the empirical formula of this compound?

CF4

A compound’s empirical formula is HO.If the formula mass is 34 grams, what is the molecular formula?

H2O2

Which of the following does not have the corresponding empirical formula XY2Z?

a.X2Y4Z2

b.XYZc.X6Y12Z6

d.X3Y6Z3

B