Chemistry: Stoichiometry Review
Answer or solve the following questions. Show all work and units!!
1. Define Avogadro’s Number & identify it.
2. Write the formula for and calculate the molar mass for the following compounds: a) Calcium Carbonate
Formula Molar Mass b) Sodium Bromide c) Potassium Sulfate d) Iron (III) Sulfide b) 59.1 g of CHCl
3 e) Carbon Dioxide
3. Calculate the number of moles, using the molar mass, of each substance. a) 0.492 g of sulfur trioxide c) 4.01 g of lithium hydroxide
4. Calculate the mass in grams, using the molar mass, of each substance. a) 1.50 mol of aluminum iodide b) 4.00 mol of glucose (C
) c) 2.27 mol of calcium nitrate
5. Calculate the number of particles or number of moles in each of the following problems. a) Find the number of molecules in 3.34 mol CO
2 b) Find the number of ions in .125 mol of Mg
2+ c) Calculate the number of moles of 3.01 x 10 d) Calculate the number of moles of 2.41 x 10
atoms of S
molecules of H
For questions 6-8, write a balanced equation and show all work!
6. How many moles of iodine are produced when 7.00 moles of chlorine gas reacts with an excess of sodium iodide?
7. When 35.9 grams of potassium chlorate is heated, it decomposes into potassium chloride and oxygen gas.
How many grams of oxygen would you expect to be produced in this reaction?
8. Iron (III) hydroxide reacts with acetic acid to form iron (III) acetate and water. If 45.4 grams of water are formed, how many moles of iron ( II I) acetate will be produced?
9. Calculate the percent composition of all elements in the compounds below. a) sodium sulfate b) potassium phosphate c) copper (II) bromide d) potassium phosphide
10. Find the empirical formulas of compounds with the following analyses. a) 32.8% Cr, 67.2% Cl b) 42.7% Co, 57.3% Se c) 56.6% La, 43.4% Cl d) 81.9% Ta, 18.1% O
Determine the empirical and molecular formulas for the following questions:
11. Chemical analysis of a sample indicates it is composed of 40.68% carbon, 5.08% hydrogen, and 54.24% oxygen and has a molar mass of 118.1g.
12. Chemical analysis of a sample indicates it is composed of 40% carbon, 6.7% hydrogen, and 53.3% oxygen and has a molar mass of 120.12g.
Mole – Volume
13. Calculate the volume of a 7.6 mole sample of H
14. What volume is occupied by 2.13 moles of N
15. A sample of H
S gas occupies a volume of 0.55 L. How many moles of H
S are present in this sample?