Chemistry Test Review: Chemical Quantities and the Mole
TO SUCCESSFULLY COMPLETE THIS TEST, YOU MUST BE ABLE TO WRITE A CORRECT CHEMICAL FORMULA!!!
A. Formula Writing Practice!
1. Write formulas for the following compounds:
a. aluminum oxide___________________
i. copper (II) phosphate ____________
b. sodium nitrite______________________
j. lithium nitride __________________
c. tetraphosphorus octaoxide_____________
k. arsenic trihydride_________________
d. sulfur difluoride ____________________
l. disilicon trichloride ________________
e. Tin (II) chloride _______________
m. Manganese (I) phosphate___________
f. lead (IV) hypochlorite___________
n. Iron (III) nitride ______________
g. potassium oxide___________
o. calcium phosphide ___________
h. calcium nitrate___________
p. strontium chlorate______________
B. From Formula Mass Notes:
2. Classify the following as an atom, ion, formula unit, or molecule.
a. CO2 ________ b. NaCl __________ c. Mg ________ d. Cl-1 _______ e. K2O__________ f. H2O___________
3. Fill in the following conversions:
a) 1 mole = ________________________g_
b) 1 mole = ___________________________ particles
c) 1 mole = _____________________L of gas
d) Formula mass of a compound = ______________ mol
4. How many oxygen atoms would be found in one formula unit of the following:
Al2(Cr2O7)3 __________________
5. What is the gram molar mass of nitroglycerin? C3H5(NO3)3?
6. What is the molar mass of sodium phosphate? (hint: write the formula correctly first!)
7. What is the gram formula mass for potassium sulfate? (hint: write the formula correctly first! I wasn’t kidding about
knowing how to write formulas for this test!!!)
C. From The Mole Notes:
8. If you were to weigh out 12.5-g of Zn, how many atoms would you have?
9. How many moles are in 45.8-g of lead (IV) nitrate, Pb(NO3)4?
10. How many formula units are in a 8.2-g wire of Na3P?
D. From Percent Composition Notes:
11. Determine the percent composition of potassium hydroxide. (hint: write the formula correctly first!)
12. Determine the percent composition of ammonium chloride. (hint: write the formula correctly first!)
From Empirical and Molecular Formula Notes:
13. When the solving empirical formula problems, there was a poem to help you. Write the poem below.
14. What’s the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen?
15. If the molar mass of the compound in problem 14 is 110 grams/mole, what’s the molecular formula?
16. What’s the empirical formula of a molecule containing 18.7% lithium, 16.3% carbon, and 65.0% oxygen?
17. If the molar mass of the compound in problem 16 above is 73.8 grams/mole, what’s the molecular formula?
Selected Answers: 5) 227 g/mol 6) 164g/mol
10) 4.94 X1022 formula units
14) C3H3O 15) C6H6O2
7) 174.3 g/mol
8) 1.15 X1023 atoms
9) 1.01 X10-1 mol
11) 69.70% / 28.52%/ 1.78%
12) 26.17% / 7.48%/ 66.36%
16) Li2CO3
17) Li2CO3