ILTS Biology: Stoichiometry & Chemical Equations 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!

Page 1

Question 1 1. Which of the following equations is balanced?

Question 2 2. How is percent yield calculated?

Question 3 3. If there are three moles of H2O for every one mole of LiClO4, then what is the hydrate formula?

Question 4 4.

Choose the correctly balanced equation for the following reaction:

Sodium + water → sodium hydroxide + hydrogen gas

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

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Question 6 6. What is the hydrate formula when there are 0.02 moles BaCl2 and 0.04 moles H2O?

Question 7 7. What does the empirical formula show?

Question 8 8. How do you determine the amount of product made?

Question 9 9. Determine the percent yield if the theoretical yield is 20 g and the actual yield is 15 g.

Question 10 10. What is NOT a step in determining the formula of a hydrate?

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Question 11 11. Which of the following calculations is NOT needed to determine the empirical formula?

Question 12 12. The starting point of a stoichiometric problem is _____.

Question 13 13. How many moles of N2 are needed to produce 18 moles NH3 in the reaction N2 + 3H2 = 2NH3?

Question 14 14. In the formula MgSO4 nH2O, what does the n before the H2O stand for?

Question 15 15. What is the percent composition of H₂SO₃?

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Question 16 16. How is mass of a substance connected to its amount in mole(s)?

Question 17 17. Select the most suitable definition for stoichiometry.

Question 18 18. 3.9g of potassium reacts with water to produce potassium hydroxide and hydrogen gas. Calculate the mass of potassium hydroxide produced.

Question 19 19. How is a mole ratio used?

Question 20 20. What is a limiting reactant?

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Question 21 21.

Choose the correctly balanced equation for the following reaction:

Potassium + water → potassium hydroxide + hydrogen gas

Question 22 22. What is the percent composition of Cu₂S?

Question 23 23. 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 24 24. What is meant by the term molar volume?

Question 25 25. Given a balanced equation involving A and B, which set of conversions must you make to change mass A to mass B?

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Question 26 26. What is the actual yield?

Question 27 27. Determine the actual yield if the theoretical yield is 12 g and the percentage yield is 90%.

Question 28 28. Where do you look to find the molar ratio?

Question 29 29. How many moles of Na are needed to produce 15 moles of NaCl in the reaction 2Na + Cl2 = 2NaCl?

Question 30 30. What is the empirical formula of a compound containing (by mass) 36.5% sulfur and 63.5% iron?

ILTS Biology: Stoichiometry & Chemical Equations 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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