Name ______Period ______
Atoms, molecules, ions, and formula units to Moles Pack
Directions: Show all of your work, including units throughout the problem and round your answers to the correct number of significant figures.
1. How many moles of K are there in 1.70 x 1022 atoms of potassium?
2. How many atoms of calcium are there in a 0.292 mole sample of calcium?
3. How many molecules of N2O are there in a 0.87 mole sample of N2O?
4. How many moles of Mn+2 are there in a 1.56 x 1023 ion sample of Mn+2?
24 5. Convert 6.47 x 10 molecules of CO2 to moles of CO2
6. How many formula units of NaCl are there in a 1.65 mole sample of NaCl?
7. How many moles of calcium nitrate are there in a 4.62 x 1023 formula unit sample of
Ca(NO3)2?
1 8. How many ions of nitride, N–3, are present in a 0.522 mole sample of N–3?
9. How many moles of N are there in 3.67 x 1022 atoms of nitrogen?
10. How many atoms of iron are there in a 1.25 sample of iron?
11. How many molecules of SF6 are there in a 1.32 mole sample of SF6?
12. How many moles of Ca+2 are there in a 3.77 x 1020 ion sample of Ca+2?
24 13. Convert 8.98 x 10 molecules of H2O to moles of H2O
14. How many formula units of SrF2 are there in a 0.65 mole sample of SrF2?
15. How many moles of Potassium Phosphate are there in a 2.05 x 1023 formula unit sample of Potassium Phosphate?
16. How many ions of Sulfide, S–2, are present in a 0.251 mole sample of S–2?
2 Grams to moles Pack
Directions: Show all of your work, including units throughout the problem and round your answers to the correct number of significant figures.
1. How many moles are there in 18.70 grams of sodium?
2. How many atoms of sodium are there in a 0.075 mole sample of sodium?
3. How many grams of sulfur are there in a 0.439 mole sample of sulfur?
4. How many moles of Mn are there in a 7.54 g sample containing Mn?
22 5. Convert 9.50 x 10 molecules of CO2 to moles.
6. How many formula units of NaCl are there in a 1.38 mole sample of NaCl?
7. How many moles are there in a 55.2 gram of nitrogen?
3 8. How many grams of Helium are present in a 3.21 mol sample of Helium?
9. How many moles of Cu atoms are in 15.7 grams of Cu atoms?
10. How many moles of Li atoms in 25.7 grams of Li atoms?
11. How many ions of sulfur are there in 25.0 mol sample of sulfur anions?
12. How many moles of C atoms are there in 25.0 grams of C atoms?
13. What is the mass of 0.984 moles of Mn atoms?.
14. How many atoms of sulfur are in 2.284 moles of S atoms?
15. What is the mass of 0.444 moles of As atoms?
4 Molar Mass and more mole conversion Pack
Determine the molar mass of the following:
1. H2O 2. Ti(MnO4)4
3. (NH4)2SO4 4. Fe3N2
Solve the problems below. Show all Work
1. Calculate the moles of CuCl2 in 157 gram sample of CuCl2.
2. Calculate the moles of Na2O in 25.7 gram sample of Na2O.
3. Calculate the mass in grams of MnO2 in 0.984 moles of MnO2.
4. Calculate the moles of SO3 molecules in 170 grams of SO3 molecules.
5 5. Calculate the mass in grams of 2.284 moles of S2Cl2.
6. Calculate the mass of 0.444 mole sample of O2.
7. How many water molecules are there in 120.0 gram sample of water?
8. What is the mass of 5.8 X 1023 formula units of Calcium chloride?
9. Calculate the mass of 2.126 moles of aluminum chloride.
10. Calculate the number of molecules of 0.125 moles of PI3.
6 Moles Review
1. How many grams are in 0.986 moles of barium sulfate, BaSO4?
2. How many moles are in 89.7g of Cl2 gas?
3. How many moles are in 79.6g of iron (II) phosphate Fe3(PO4)2?
4. How many grams are in 9.87 X1024 formula units of calcium sulfide, CaS?
2 22 5. How many moles of copper (II) chlorate, Cu(ClO3) are there in a 4.39 x 10 formula unit sample of copper (II) chlorate?
7 6. How many moles are in 6.89 X 1022 formula units of lead (IV) Sulfite
Pb(SO3)2?
7. How many formula units are in in 95.6 g of lead (IV) carbonate Pb(CO3)2?
8. How many moles are in 36.7 grams of Strontium Chloride (SrCl2)?
8 Percentage Composition Worksheet
Give the % composition of all elements in these compounds. Show all work!
1) ammonium sulfite % N ______
% H ______
% S ______
% O ______
2) aluminum acetate % Al ______
% C ______
% H ______
% O ______
3) sodium bromide % Na ______
% Br ______
4) copper (II) hydroxide % Cu ______
% O ______
% H ______
5) magnesium carbonate % Mg ______
% C ______
% O ______
9 Review Mole Problems
22 1. How many moles of copper (II) chlorate, Cu(ClO3)2 are there in a 4.39 x 10 formula unit sample of copper (II) chlorate?
How many grams of copper are in this sample of Cu(ClO3)2?
2. How many grams are in 0.986 moles of barium sulfate BaSO4?
3. How many grams of silver chloride are in 1.96 moles of silver chloride, AgCl?
4. How many moles of iron are in 79.6g of iron (II) phosphate Fe3(PO4)2?
5. How many grams of calcium are in 9.87 X1024 formula units of calcium sulfide, CaS?
10 Empirical Formulas Determine the empirical formula for the following compositions: 1. 88.8% copper, 11.2% oxygen
2. 40.0% carbon, 6.7% hydrogen, 53.3% oxygen
3. 92.3% carbon, 7.7% hydrogen
4. 70.0% iron, 30.0% oxygen
11 5. 5.88% hydrogen, 94.12% oxygen
Solve the problems below: 6. A compound is analyzed and found to contain 5.64g of magnesium and 16.36g of chlorine. Calculate the empirical formula.
7. A salt of barium is found to contain 17.14g of barium and 8.86g of chlorine. What is the simplest formula (empirical formula)?
12 Empirical & Molecular Formula Worksheet
Directions: Show all of your work in the following problems, and include units for molar mass, where necessary.
1) What’s the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen?
2) If the molar mass of the compound in problem 1 is 110 grams/mole, what’s the molecular formula?
3) What’s the empirical formula of a molecule containing 18.7% lithium, 16.3% carbon, and 65.0% oxygen?
4) If the molar mass of the compound in problem 3 is 73.8 grams/mole, what’s the molecular formula?
13 5) The molar mass for a compound is 228.0 g/mol. Determine the molecular formula for this compound when the empirical formula is C2H4O3.
6) The molar mass for a compound is 165.0 g/mol. Determine the empirical and molecular formulas for the compound when it contains 8.5 grams of nitrogen, 3.0 grams of hydrogen, and 21.8 grams of carbon.
7) Determine the empirical formula for a compound that contains 20.5% C, 2.5% H, 53.8%O, and the remaining percentage is nitrogen. If the molar mass of the compound is 595.0 g/mol, what is the molecular formula for the compound?
14 Chapter 8 Review SOLVE THE FOLLOWING MOLAR CONVERSION & MOLARITY PROBLEMS: 21 1. How many grams would 8.1 x 10 molecules of sucrose (C12H22O11) weigh?
2. How many grams of AgNO3 are in 0.80mol of AgNO3? 3. How many moles are in 53.8 g of magnesium chloride?
4. How many formula units of SrSO4 are in 23.1 grams?
5. How many formula units are in 0.845 moles of NaNO3? 6. How many molecules are in 50.0 g of sulfur trioxide?
SOLVE THE FOLLOWING PERCENTAGE COMPOSITION PROBLEMS:
7. Find the percentage composition of carbon in sucrose (C12H22O11). 8. Find the percentage composition of nitrogen in nitrogen monoxide.
SOLVE THE FOLLOWING EMPIRICAL & MOLECULAR FORMULA PROBLEMS: 9. Find the empirical formula of a compound that contains 75% carbon and 25% hydrogen. 10. Find the empirical formula of a compound that contains 9.03 g magnesium and 3.48 g of nitrogen.
11. The empirical formula of a compound is NO2. Its molecular mass is 92 g/mol. What is its molecular formula?
12. Glucose has an empirical formula of CH2O. Find its molecular formula if its molecular mass is 180.0 g/mol. 13. A compound is composed of 34.2% sodium, 17.7% carbon, and 47.6% oxygen. Find its empirical formula. If its molecular mass is 134 g/mol, find its molecular formula.
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