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Stoichiometry Calculations: Help & Review Chapter Exam

Exam Instructions:

Choose your answers to the questions and click 'Next' to see the next set of questions. You can skip questions if you would like and come back to them later with the yellow "Go To First Skipped Question" button. When you have completed the practice exam, a green submit button will appear. Click it to see your results. Good luck!

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Question 1 1. The starting point of a stoichiometric problem is _____.

Question 2 2. How is mass of a substance connected to its amount in mole(s)?

Question 3 3. How many moles of Na are needed to produce 15 moles of NaCl in the reaction 2Na + Cl2 = 2NaCl?

Question 4 4. Determine the actual yield if the theoretical yield is 12 g and the percentage yield is 90%.

Question 5 5. If 4.0 moles of HCl react with 5.0 moles of NaOH to make NaCl and H2 O in the equilibrium reaction HCl+ NaOH = NaCl + H2 O, what is the limiting reactant?

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Question 6 6. You conduct an experiment that requires the creation of an ammonia solution. You do this by reacting 50.0 L of nitrogen gas with excess hydrogen gas at STP to create ammonia gas using the Haber process given by the following reaction: N2 (g) + 3H2 (g) → 2NH3 (g). Assuming the reaction had 100% yield, you then bubble the ammonia into 5.0 L of water. What is the molarity of the resulting ammonia solution?

Question 7 7. How is a mole ratio used?

Question 8 8. What is the percent composition of Cu₂S?

Question 9 9. At STP, how much space (in liters) will 0.750 moles of argon gas occupy?

Question 10 10. In the formula MgSO4 nH2 O, what does the n before the H2 O stand for?

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Question 11 11. What is the difference between a hydrate and an anhydrate?

Question 12 12. If 1.605 kg of mercury are used in the reaction 2Hg + O2 --> 2HgO, what is the mass of HgO, in kilograms, that are produced?

Question 13 13. If there are three moles of H2 O for every one mole of LiClO4, then what is the hydrate formula?

Question 14 14. How is percent yield calculated?

Question 15 15. Where do you look to find the molar ratio?

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Question 16 16. How many moles of solute are in a 0.50 L solution of 3.0 molarity?

Question 17 17. 3.9g of potassium reacts with water to produce potassium hydroxide and hydrogen gas. Calculate the mass of potassium hydroxide produced.

Question 18 18. What is the hydrate formula when there are 0.02 moles BaCl2 and 0.04 moles H2 O?

Question 19 19. Given a balanced equation involving A and B, which set of conversions must you make to change mass A to mass B?

Question 20 20. Which of the following mole ratio is NOT appropriate to the equation 6CO2+ 6H2 O = C6 H12 O6+ 6O2?

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Question 21 21. How do you determine the amount of product made?

Question 22 22. What is theoretical yield?

Question 23 23. How many moles of N2 are needed to produce 18 moles NH3 in the reaction N2 + 3H2 = 2NH3?

Question 24 24. What is the percent composition of H₂SO₃?

Question 25 25. What is a limiting reactant?

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Question 26 26. Say you take a reactant A and calculate the amount of moles of another reactant B required to use up all of A. How do you know which of two reactants is the limiting one?

Question 27 27. Which of the following calculations is NOT needed to determine the empirical formula?

Question 28 28. What does the empirical formula show?

Question 29 29. Determine the percent yield if the theoretical yield is 20 g and the actual yield is 15 g.

Question 30 30. If 2.5 moles of zinc react with 6.0 moles of hydrochloric acid in the equation Zn + 2HCl = ZnCl2 + H2, what is the limiting reactant?

Stoichiometry Calculations: Help & Review Chapter Exam Instructions

Choose your answers to the questions and click 'Next' to see the next set of questions. You can skip questions if you would like and come back to them later with the yellow "Go To First Skipped Question" button. When you have completed the practice exam, a green submit button will appear. Click it to see your results. Good luck!

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