Moles WS 5
Chapter 11 – Supplemental Problems - The Mole
1. Identify and calculate the number of representative
particles in each of the following quantities.
4. Calculate the number of moles in each of the
following quantities.
a. 2.14 moles of gold
a. 6.35 g lithium
b. 0.151 mole of nitrogen monoxide (NO)
b. 346 g zinc
c. 11.5 moles of potassium bromide (KBr)
c. 115 g nickel
2. Calculate the number of moles in the substance that
contains the following number of representative
particles.
5. How many atoms are in the following samples?
a. 1.24 g cobalt
a. 8.92 x 1023 atoms of barium
b. 0.575 g cesium
b. 5.50 x 1025 molecules of carbon monoxide (CO)
c. 2.66 x 1022 formula units of potassium iodide (KI)
3. Determine the mass in grams of each of the
following quantities.
c. 65.6 g silicon
6. Which quantity has the greatest mass?
a. 1.24 moles beryllium
a. 4.16 x 1023 atoms of radium
b. 3.35 moles of calcium
b. 1.50 x 1020 atoms of cadmium
c. 0.155 mole of sulfur
c. 1.33 x 1022 formula units of potassium iodide
Supplemental Problems
Transcribed by Zachary M Sohn
Chemistry: Matter and Change
Chapter 11
1
Moles WS 5
7. Determine the molar mass of each of the following
compounds.
Use binder paper for the next three problems:
11. Determine the empirical formula for a 100.00-g
sample of a compound having the following percent
composition.
a. formic acid (CH2O2)
a. 94.07% sulfur and 5.93% hydrogen
b. ammonium dichromate ((NH4)2Cr2O7)
b. 80.68% mercury, 12.87% oxygen,
and 6.45% sulfur
8. What is the mass in grams of each of the following
quantities?
12. A 48.30-g sample of an aluminum-iodide
compound contains 3.20 g of aluminum. What is
the empirical formula for the compound?
a. 2.53 moles of lead(II) nitrate (Pb(NO3)2)
13. Caffeine is a compound found in some natural
coffees and teas and in some colas.
b. 4.62 moles of magnesium bromide (MgBr2)
a. Determine the empirical formula for caffeine,
using the following composition of a 100.000-g
sample.
9. Calculate the number of moles in each of the
following samples.
a. 3.75 g calcium carbide (CaC2)
49.47 grams of carbon, 28.85 grams of nitrogen,
16.48 grams of oxygen, and 5.20 grams of
hydrogen
b. If the molar mass of caffeine is 1964.19g/mol,
calculate its molecular formula.
b. 245 g aluminum nitrite (Al(NO2)3)
10. Determine the percent of composition of each of the
following compounds.
You may need to use binder paper to
have enough room to answer these last
few questions.
a. manganese(II) oxide (MnO)
b. propanol(C3H8O)
c. calcium phosphate (Ca3(PO4)2)
Supplemental Problems
Transcribed by Zachary M Sohn
Chemistry: Matter and Change
Chapter 11
2