AP Chemistry: Stoichiometry and Chemical Equations: Help and 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. Which of the following calculations is NOT needed to determine the empirical formula?

Question 2 2. Determine the actual yield if the theoretical yield is 12 g and the percentage yield is 90%.

Question 3 3. How is percent yield calculated?

Question 4 4. What is the hydrate formula when there are 0.02 moles BaCl2 and 0.04 moles H2 O?

Question 5 5. What is the difference between a hydrate and an anhydrate?

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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. Which of the following equations is balanced?

Question 8 8. What is a limiting reactant?

Question 9 9. The starting point of a stoichiometric problem is _____.

Question 10 10. How is a mole ratio used?

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Question 11 11. What is NOT a step in determining the formula of a hydrate?

Question 12 12. What is the empirical formula of a compound containing (by mass) 36.5% sulfur and 63.5% iron?

Question 13 13. 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 14 14.

Choose the correctly balanced equation for the following reaction:

Sodium + water → sodium hydroxide + hydrogen gas

Question 15 15. 3.9g of potassium reacts with water to produce potassium hydroxide and hydrogen gas. Calculate the mass of potassium hydroxide produced.

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Question 16 16. What is a coefficient?

Question 17 17. How many moles of solute are in a 0.50 L solution of 3.0 molarity?

Question 18 18. At STP, how much space (in liters) will 0.750 moles of argon gas occupy?

Question 19 19. 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?

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

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Question 21 21. Select the most suitable definition for stoichiometry.

Question 22 22. In the formula MgSO4 nH2 O, what does the n before the H2 O stand for?

Question 23 23. What is the volume of 2 moles of a gas at 300K and 1.25atm?

Question 24 24. 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 25 25. How many moles of N2 are needed to produce 18 moles NH3 in the reaction N2 + 3H2 = 2NH3?

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Question 26 26. How is mass of a substance connected to its amount in mole(s)?

Question 27 27. What is the percent composition of H₂SO₃?

Question 28 28. What is the percent composition of Cu₂S?

Question 29 29. What is theoretical yield?

Question 30 30. 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?

AP Chemistry: Stoichiometry and Chemical Equations: Help and 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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