PRACTICE FOR MIDTERM 2:

Please note that these questions were made to understand concepts I think are worthy of knowing before the exam. Please note that I have not seen any previously made exams and you SHOULD NOT only rely on this practice as preparation for the test. I highly recommend working through the Tro problems that the teacher assigned as well as reading the book/powerpoints. I also made these questions multiple choice AND free response to reflect the testing style of the teacher.

TOPICS

CHAPTER 4

Writing and Balancing Chemical Equations (Q1) Reaction Stoichiometry (Q2) Limiting Reagents and Theoretical/Percent Yield (Q3) Chemical Reactions and Chemical Quantities (Q8)

CHAPTER 5

Solution Concentration, Dilution, and Stoichiometry (Q4, Q5, Q22) Aqueous Solutions and Solubility (Q6) Precipitation Reactions and Ionic Equations (Q7) Acid/Base Reactions (Q9, Q10) Oxidation/Reduction Reactions (Q11, Q12, Q13)

CHAPTER 6

Simple Gas Laws and Ideal Gas Laws (Q14, Q15, Q17) Partial Pressures and Mole Fractions (Q 16) Kinetic Molecular Theory (Q18) Diffusion and Effusion of Gases (Q19, Q23)

Additional practice:

Significant Figures (Q20, Q21)

1. Balance the following equation: __ Ba₃N₂ + __ H₂O → __ Ba(OH)₂ + __ NH₃

2. How many moles of NH3 form when 4.88kg of N2H4 react? 3 N2H4 (l) 4 NH3 (g) + N2 (g)

3.

What is the theoretical yield of C6H5Br if 42.1g of C6H6 reacts with 73.0g of Br2? C6H6 + Br2 C6H5Br + HBr

If the actual yield of C6H5Br is 63.6g, what is the percent yield?

4. If 4.95g of ethylene (C2H4) is combusted with 3.25g of oxygen, what is the limiting reagent? How many grams of CO2 are formed?

5. If you dilute 175mL of a 1.6M solution of LiCl to 1.0L, determine the new concentration of the solution.

6. Calculate the volume of solution prepared by diluting 6.929mL solution if 3.555M solution to .8229M.

7. HBr, HCl, HClO4, KBr, and NaCl are all classified as … a. Strong electrolyte b. Weak electrolyte c. Nonelectrolyte d. Acids

8. Determine the physical states of the products and write a net ionic equation for the following reaction:

Pb(NO3)2 (aq) + 2 NaI (aq) → PbI2(___) + 2 NaNO3 (___)

9. What type of reaction is each of the following? o HCl (aq) + NH3(aq) → NH4Cl(aq)

o MgCl2(aq) + 2 KOH(aq) → 2 KCl(aq) + Mg(OH)2(aq)

o 2 HCl(aq) + Ca(s) → CaCl2(aq) + H2(g)

o HCl(aq) + AgNO3(aq) → AgCl(s) + HNO3(aq)

o Zn(s) + CuCl2(aq) → ZnCl2(aq) + Cu(s)

10. What is true about a neutralization reaction?

a. It forms an acid and a base b. It forms a salt in water c. It forms a solid d. It forms only neutral molecules

11. What is the oxidation number of the underlined atom? a) NaNO3 b) BaSO3

12. In the following reaction, identify the species being oxidized and the oxidizing agent.

3 Hg2+ + 2 Fe (s) ---> 3 Hg2 + 2 Fe3+

13. Determine the components of the following redox reaction: 3 Ag+ (aq) + Al (s) 3 Ag (s) + Al3+

(aq)

14. According to Boyle’s Law, the pressure of a gas is inversely proportional to its _______ Temperature Amount of gas in moles (n) Volume Weight

15. If you have an unknown quantity of gas held at a temperature of 1195 K in a container with a volume of 25 liters and a pressure of 560 atm, how many moles of gas is there?

16. A mixture of three gases in a balloon is able to generate 2 atm of pressure. The identities and amounts of each gas are as follows. 2 moles of O2, 3 moles of N2, 5 moles of H2. What is the partial pressure of Oxygen gas?

17. 4NH3(g)+7O2(g)→4NO2(g)+6H2O(l)

According to the above reaction, what volume of NO2(g) is produced from the combustion of 100 g of NH3(g), assuming the reaction takes place at standard temperature and pressure?

18. Place the following gases in order of increasing average velocity at 400K: Ne, Ar, SO2, N2

a. Ar < Ne < N2 < SO2

b. Ne < Ar < N2 < SO2

c. N2 < SO2 < Ne < Ard. Ne < Ar = N2 < SO2

e. SO2 < Ar < N2 <Ne

19. Rank the following in from fastest rate of effusion to slowest: CO, F2, SF6, Kra. Kr > CO > SF6 > F2

b. F2 > Kr > CO > SF6

c. CO > F2 > Kr > SF6

d. CO > F2 > SF6 > Kre. SF6 > Kr > F2 > CO

20. The measurement, 0.0020600 mole, has how many significant digits?

21. What is the answer in significant digits of: 500. x 0.6795 + 2005?

22. Find the molarity when 0.5 moles of sodium chloride is dissolved to make 0.05 L of solution

23.

Which has the slowest rate of effusion?

a. O2

b. N2

c. Hed. H2