2 nd Semester Final Exam Practice Test Questions 30 minutes

1. Which does NOT indicate a phase change? A. A piece of aluminum is heated to it melting point. B. A liquid is cooled slowly until it turns into a solid. C. A rock is crushed into a fine sand D. Water is left in a cup and slowly dissappears. 25 Seconds

2. What affects the speed of a chemical reaction by decreasing the activation energy of the reaction? A. Temperature B. Catalyst C. Grinding D. Stirring 20 Seconds

3. What phase(s) of matter is present at.9 atm & 50 ⁰C ? A. Solid B. Liquid C. Gas 25 Seconds

4. What is the relationship between Avogadro’s number and H 2 O? A g of H 2 O B L of H 2 O C X particles of H 2 O 15 Seconds

5. How much heat is lost to change 12.5 g of H 2 O (4.184 J/g(°C)) from 80.0°C to 50.0°C? A J B J C J D J 1 minute; 15 seconds

6. What is the change in temperature if 95.3 g sample of water gains 1250 J of energy? Remember the specific heat of water is J/g(°C) A °C B. 28,471.6 °C C °C D °C 1 minute; 15 seconds

7. What is the pressure at the normal melting and boiling point of water? A.0 atmC atm B.1 atmD. 225 atm 20 Seconds

8. Is the process when a gas changes into a liquid endothermic or exothermic? H 2 O (g)  H 2 O (l) A. Endothermic B. Exothermic 15 Seconds

9. What change takes place when gas at.8atm & 100 ⁰ C is cooled to 50 ⁰ C? A.FreezesC. Sublimes B.CondensesD. Vaporizes 25 Seconds

10. What is the molar volume of a gas? A g B L C X particles 15 Seconds

11. How many grams are in 2.5 moles of BrO 2 ? A grams B. 280 grams C grams D. 240 grams 1 minute

12. What is the molar mass of H 2 SO 4 ? A grams B grams C grams D grams 45 seconds

13. Reduction is the process by which a substance _____________. A. Loses one or more electrons B. Gains one or more electrons C. Gains one electron D. Loses one electron 20 seconds

14. Calculate the molarity of a 50.0 g sample of NaCl that is mixed in 150mL of water. A M B..13 M C..13 m D. 5.7 M 1 minutes 15 seconds

15. Using the equation below, how many grams of NaOH are needed to produce 30.8 L of Na 2 SO 4 ? H 2 SO 4 + 2NaOH  2H 2 O + Na 2 SO 4 A g B g C g D g 1 minute and 30 seconds

16. Using the equation below, how many grams of H 2 SO 4 will you get if you have 58.5 g of NaOH? H 2 SO 4 + 2NaOH  2H 2 O + Na 2 SO 4 A g B. 143 g C. 287 g D g 1 minute 30 seconds

17. Base off of Charles’ Law, what happens to a balloon when the temperature is decreased? A. The balloon popped B. The balloon got bigger (increase volume) C. The balloon got smaller (decrease volume) D. The balloon volume didn’t change. 25 seconds

18. How much heat will be released if 9.0 g of Na reacts with excess O 2 ? 2Na + O 2  Na 2 O  H = -60 kJ A. 23 kJ B. -23 kJ C. 12 kJ D. -12 kJ 1 minute 15 seconds

19. A gas mixture contains the following gases with the mole fractions indicated: CH 4 (0.380), C 2 H 6 (0.325), C 3 H 8 (0.009), and C 4 H 10 (0.057). The mixture also contains C 2 H 2. What is the mole fraction of C 2 H 2 ? A X B C D seconds

20. A sealed plastic bottle has a volume of 2 L at a temperature of 35°C, what is the temperature if the volume decreases to 1.5 L? A. -42°C B. 17°C C. 231°C D..09°C 1 minute

21. A 20. L balloon at standard atmospheric pressure is squeezed and causes a new pressure of 900. mmHg. What is the new volume of the balloon? A. 17 L B..020 L C. 24 L D..87 L 1 minute

moles of a gas at 2.3 atm is in a 4.5 L container. What is the temperature of the gas? A. 84 ⁰ C B. 84 K C. 16 ⁰ C D. 16 K 1 minute 15 seconds

23. What is the % by mass of Mn in MnO 4 ? A. 76.3% B. 76.4% C. 46.2% D. 49.1% 1 minute 15 seconds

24. According to Le Chatelier’s principle, a decrease in the concentration of a product will cause a reaction to: A. shift to the left B. shift to produce more of the reactants C. consume what is left of the products D. shift to produce more of the products 30 seconds

25. What is the pH of M Sr(OH) 2 A B..222 C..523 D Seconds

26. Systems in nature tend to undergo changes toward A. higher entropy and higher energy B. lower entropy and lower energy C. higher entropy and lower energy D. lower entropy and higher energy 20 Seconds

27. Fe + 3Cl 2  2FeCl 3 Which way does the reaction shift when you take away some FeCl 3 A. Left B. Right C. No Shift 20 seconds

28. Fe + 3Cl 2  2FeCl 3 Which will result in an increase in concentration of FeCl 3 ? A. Decrease Fe B. Decrease the pressure C. Increase Cl 2 D. Change the temperature 20 seconds

29. In a direct combination reaction, A. an element is reduced and the other one is oxidized B. all elements are oxidized C. all elements are reduced D. it has nothing to do with a redox reaction 20 seconds

30. Which of the following is a property of an acid? A. Bitter taste B. Slippery C. Good conductor of electricity D. Soothes sunburns 15 seconds

31. The kinetic molecular theory assumes that the particles of an ideal gas A. Exert no force on one another B. Have a volume close to 1 C. Exert great forces on each other during collisions A. Move in specific patterns 25 seconds

32. A weak acid... A. totally dissociates in water B. doesn’t conduct electricity C. produces H + ions that form H 3 O + ions D. makes the water basic 15 seconds

33. The end point and equivalence point in an acid base reaction should be A. at the same point B. at a difference of 1 C. have pH’s of 6 and 8 D. a point with a concentration of 1.0 M 15 seconds

34. Which is a neutralization reaction? A. when a carbon compound burns in O 2 B. when a molecule splits into its parts C. when a single replacement reaction takes place. D.when H + ions react with OH - ions 20 seconds

35. In the following reaction, label the oxidation state (number) of each element before and after the reaction: 2 C 2 H O 2  4 CO H 2 O H = O = C = 1 ½ minutes

36. Based off of your answers to the previous question, what element(s) are being reduced when the product is produced? Oxidized? 2 C 2 H O 2  4 CO H 2 O A. reduced = C, oxidized = O B. reduced = O, oxidized = C C. reduced = H, oxidized = O D. reduced = O, oxidized = H 30 sec

37. A sample of HCl is considered to be an Arrhenius acid because it dissolves in water to yield A. OH + ions as the only positive ions B. HCl molecules to make it acidic C. Cl - ions as the only negative ions D.H + ions as the only positive ions 20 seconds

38. What is the hydronium ion concentration when a solution changes from a pH of 6 to 2? A. 10,000 times the original content B. 1,000 times the original content C. 100 times the original content D.10 times the original content 45 seconds

Answer Key 1.C7. B13. B19. D25. D31. A 2. B8. B14. D20. A26. C32. C 3. B9. B15. A21. A27. B33. A 4. C10. B16. A22. B28. C34. D 5. C11. B17.C23. C29. A 6. C12. A18. D24. D30. C

Answer Key 38. A 35. H = +1 & +1 O = 0 & -2 C = -1 & B 37. D