Name Practice Test 2 Chemistry 111 1) In the aqueous reaction of K 2 SO 4 (aq) + Ba(NO 3 ) 2 (aq) BaSO 4 (s) + 2KNO 3 (aq), which ions are the spectator ions? A) Ba 2+ 2- and SO 4 B) Ba 2+ and K + C) Ba 2+ - and NO 3 D) K + 2- and SO 4 E) K + - and NO 3 2) Which of the following choices represents the net reaction which actually takes place in solution when the strong acid HCl (aq) is added to Ba(OH) 2 (aq)? A) HCl (aq) + Ba(OH) 2(aq) BaCl 2(aq) + H 2 O (l) B) H + + OH - H 2 O (l) C) HCl (aq) + OH - Cl - + H 2 O (l) D) H + + Ba(OH) 2(aq) Ba 2+ + H 2 O (l) E) HCl (aq) + Ba 2+ BaCl 2(aq) + H + 3) Vinegar contains a weak acid, acetic acid (HC 2 H 3 O 2 ), which is responsible for its acidity. In one analysis of a commercial vinegar brand, a 15.0 ml sample was titrated with 0.4500 M NaOH. It required 30.50 ml of this NaOH solution to neutralize the acid in the vinegar sample. What is the molar concentration of acetic acid in vinegar? A) 0.102 M B) 0.221 M C) 0.305 M D) 0.458 M E) 0.915 M 4) The volume of 0.200 M K 2 CO 3 solution that contains 69.0 g of K 2 CO 3 is: A) 0.400 L B) 200 ml C) 1.60 L D) 500 ml E) 2.50 L
5) Given the following unbalanced reaction: V 2 O 5 + C + Cl 2 VOCl 3 + COCl 2 When properly balanced, the equation shows that for every one mole of VOCl 3 formed mole(s) of carbon are required. A) 1 B) 3/2 C) 2 D) 5/2 E) 3 6) Which of the following compounds should be insoluble in water? A) AgNO 3 B) Na 2 CO 3 C) PbS D) Na 2 S E) NH 4 Cl 7) The correct complete ionic equation for the reaction that occurs when aqueous solutions of Ca(NO 3 ) 2 and Na 2 CO 3 are mixed is A) Ca(NO 3 ) 2 (aq) + Na 2 CO 3 (aq) ----> CaCO 3 (s) + 2 NaNO 3 (aq) B) Ca 2+ (aq) + 2 NO 3 - (aq) + 2 Na + (aq) + CO 3 2- (aq) ----> CaCO 3 (s) + 2 Na + (aq) + 2 NO 3 - (aq) C) Ca 2+ (aq) + 2 NO 3 - (aq) + 2 Na + (aq) + CO 3 2- (aq) ----> Ca 2+ (aq) + CO 3 2- (aq) + 2 NaNO 3 (s) D) Ca 2+ (aq) + CO 3 2- (aq) ----> CaCO 3 (s) E) Na + (aq) + NO 3 - (aq) ----> NaNO 3 (s) 8) Which of the following is a neutralization reaction? A) HCl(aq) + AgNO 3 (aq) ----> AgCl(s) + HNO 3 (aq) B) CuSO 4 (aq) + Zn(s) ----> ZnSO 4 (aq) + Cu(s) C) 2 K(s) + 2 H 2 O(l) ----> 2 KOH(aq) + H 2 (g) D) H 2 SO 4 (aq) + 2 NaOH(aq) ----> 2 H 2 O(l) + Na 2 SO 4 (aq) E) None of the above. 9) What is the oxidation number of Cr in K 2 Cr 2 O 7? A) +12 B) +3 C) +4 D) +5 E) +6
10) In which of the following reactions does an oxidation-reduction process occur? A) HCl(aq) + AgNO 3 (aq) ----> AgCl(s) + HNO 3 (aq) B) CuSO 4 (aq) + Zn(s) ----> ZnSO 4 (aq) + Cu(s) C) 2 K(s) + 2 H 2 O(l) ----> 2 KOH(aq) + H 2 (g) D) 2 HCl(aq) + Ca(OH) 2 (aq) ----> 2 H 2 O(l) + CaCl 2 (aq) E) B and C 11) What volume of 3.0 M NaOH can be prepared using exactly 96.0 g of NaOH? (MM NaOH = 40.0 g/mol) A) 0.14 L B) 0.70 L C) 0.80 L D) 1.25 L E) 7.20 L 12) What volume of water must be added to 300 ml of 0.75 M HCl to dilute the solution to 0.25 M? A) 900 ml B) 600 ml C) 300 ml D) 930 ml E) 100 ml 13) The limiting reagent is the substance: A) present in greatest quantity B) limits the number of reagents present C) determined by the amount of reactants present D) that determines the maximum amount of possible product 14) Write the overall molecular equation and the net ionic equation when the following aqueous reagents are mixed: A) silver (I) chlorate is added to sodium chromate
B) Nitrous acid, a weak acid with the formula HNO 2, reacts with Ca(OH) 2 C) Hydrobromic acid reacts with potassium hydroxide 16) Please show all of your work on this problem to receive full credit. Hydrochloric acid can be prepared by the following (unbalanced) reaction: NaCl(s) + H 2 SO 4 (aq) HCl(g) + Na 2 SO 4 (aq) A) How many grams of HCl can be prepared from 3.00 mol H 2 SO 4 and 140 g NaCl? B) At the end of the reaction, how much of each reactant remains? C) If the reaction yield is really only 75%, how much HCl will actually be prepared?
1. Which of the following is true for a gas at STP? a. 0 atm b. 0 C c. 25 C d. 25 atm 2. Which of the following reactions is likely exothermic? a. decomposition of carbon dioxide b. formation of hydrogen bromide c. formation of propane d. b and c 3. What does ΔH = -98.3 kj/mol for CH 4 (g) + Cl 2 (g) CH 3 Cl (g) + HCl (g) tell us about the reaction? a. The reaction is product-favored at room temperature b. The reaction is exothermic c. The reaction is endothermic d. a and b 4. If the reaction above is reversed and uses 3.3 moles HCl, what is ΔH? a. +98.3 kj b. -324.4 kj c. +324.4 kj d. -98.3 kj 5. What is ΔH for the reaction in #4 for 25.0 g of methane? a. +163.4 kj b. -163.4 kj c. +2457.5 kj d. +2457.5 kj 6. What happens when dry ice (carbon dioxide) sublimates? a. Energy is released. b. Energy is absorbed. c. Need more information. d. Neither a or b. 7. If 2.5L of gas at 99843 Pa is reduced to a volume of 1.5, what is the new pressure in atm? (5 pts)
8. Calculate the enthalpy change (kj/mol) for the formation of one mole of carbon monixide according to this reaction: (10 pts) C (s) + H 2 O (g) CO ( g) + H 2 (g) using the following information: ΔH C (s) + O 2 (g) CO 2 (s) -393.5 kj 2 CO (g) + O 2 (g) 2 CO 2 (g) -566.0 kj 2 H 2 (g) + O 2 (g) 2 H 2 O (g) -483.6 kj You must use the information above for credit on this question. 14. Consider the following unbalanced reaction: Fe (s) + HCl (aq) FeCl 2 (aq) + H 2 (g) What volume (in liters) of hydrogen gas at STP is released by mixing 5.34 g of iron with 5.00 ml of 1.250 M HCl? (15 pts) 15. Calculate ΔH in kj/mol for the combustion of acetylene, C 2 H 2, using standard heats of formation. Assume that any water formed will be a vapor. (10 pts)