1. CHEM 1411 – S.I. PRACTICE TEST 2
EXAM 2 – Chapter 3, 4 & 7
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) When the following equation is balanced, the coefficient of Al2O3 is____________.
Al2O3 (s) + C (s) + Cl2 (g) → AlCl3 (s) + CO (g)
A) 2 B) 5 C) 4 D) 1 E) 3
2) Which of the following is soluble in water at 25°C?_______________.
A) Fe3(PO4)2 B) FeS C) Fe CO3 D) Fe(OH)2 E) Fe(NO3)2
3) The mass % of C in methane is _____________.
A) 7.743 B) 133.6 C) 74.87 D) 92.96 E) 25.13
4) What is the coefficient of O2 when the following equation is completed and balanced?
C2H6 + O2 → ______________
A) 6 B) 3 C) 5 D) 2 E) 7
5) What is the coefficient of H3PO4 when the following equation is completed and balanced?
H3PO4 (aq) + NaOH (aq)
A) 2 B) 3 C) 0 D) 1 E) -5
6) The formula weight of ammonium sulfate, (NH4)2SO4 , is _______ amu.
A) 132 B) 116 C) 119 D) 264 E) 100
7) A compound contains 40.0% C, 6.71% H, and 53.29% O by mass. The molecular weight of the compound is 60.05 amu. The
molecular formula of this compound is _______________.
A) C2H4O2 B) CH2O C) CHO2 D) C2H2O4 E) C2H3O4
8) Convert the following to a balanced chemical reaction: Gaseous hydrogen reacts with carbon monoxide to form methanol, CH3OH.
A) 2H2 + CO2 → CH3OH B) 4H + CO → CH3OH
C) H2 + CO → CH3OH D) 2H2 + CO → CH3OH
9) Calculate the number of molecules in 172 g of table sugar, C12H22O11.
A) 1.85 x 1022 B) 6.02 x 1023 C) 3.60 x 1024 D) 3.01 x 1023
10) How many moles in 172g of table sugar, C12H22O11.
A) 0.500 B) 1.00 C) 3.00 D) 12.0
11) How many Carbon atoms in 172 g of table sugar C12H22O11.
A) 1.85 x 1022 B) 6.02 x 1023 C) 3.60 x 1024 D) 3.01 x 1023
12) If 4.0 moles of Li and 2.0 moles of O2 are used in the reaction Li + O2 Li2O, then the limiting reactant is ___________ and the
theoretical yield of Li2O is ___________g.
A) oxygen, 6.0 x 10 B) oxygen, 1.2 x102 C) lithium, 3.0 x 10 D) lithium, 6.0 x 10
2. 13) In a certain experiment 5.4 g Al was reacted with excess oxygen and 5.1 g of aluminum oxide was obtained. What was the
percent yield of the reaction?’
A) 50 percent B) 68 percent C) 78 percent D) 94 percent
14) Hoe many milliliters of 0.1000 M Ca(OH)2 solution are needed to supply 0.05000 mol of Ca(OH)2?
A) 1000. mL B) 2000. mL C) 250.0 mL D) 500.0 mL
15) Indicate the concentration of each ion or molecule present in a 0.25 M CaBr2 solution.
A) 0.50 M Ca2+, 0.25 M Br B) 0.25 M Ca2+, 0.50 M Br
C) 0.25 M CaBr2 D) 0.25 M Ca2+, 0.25 M Br
16) Which of the following reactions is an acid-based neutralization reaction?
A) Ca(OH)2 (aq) + 2HI (aq) CaI2 (aq) + 2H2O (l)
B) 2Na(s) 2H2O (l) H2(g) +2NaOH(aq)
C) Na3PO4(s) +H2O 3Na+ (aq) + PO43-(aq)
D) AgNO3(aq) + NaI(aq) AgI(s) + NaO3(aq)
17) Write a balanced net ionic equation for the following reaction and identify the spectator ion(s) present.
FeO(s) +HClO4(aq) H2O (l) + Fe(ClO4)2 (aq)
A) FeO(s) +2H+(aq) H2O(l) + Fe2+(aq) ; ClO4-, and Fe2+ spectator ions
B) FeO(s) +2H+(aq) H2O(l) + Fe2+(aq) ; ClO4- spectator ion
C) FeO(s) +2H+(aq) 2 ClO4- (aq) H2O (l) + Fe2+ (aq) + 2ClO4- (aq); ClO4- spectator ion
D) FeO(s) +2HClO4- (aq) H2O (l) + Fe(ClO4)2 (aq) ; no spectator ions
18) When NaCl is added to a solution of (i) AgNO3, (ii) Pb(NO3)2, or (iii) Ca(NO3)2, in which case(s) does a precipitate form?
A) Ca(NO3)2 only B) Pb(NO3)2 only
C) AgNO3 and Pb(NO3)2 only D) AgNO3 only
19) Write a balanced equation for the reaction, if any, that may occur when the following pair is mixed: Pb(NO3)2 (aq) and MgSO4(aq).
A) Mg+(aq) + NO3-(aq) MgNO3(s) B) Mg2+(aq) + 2NO3-(aq) Mg(NO3)2(s)
C) Pb2+(aq) + SO4-(aq) PbSO4(aq) D) AgNO3 only
20) If 200 mL of a 2.50 M NaOH solution is diluted to 500. mL, what is the new concetration of NaOH?
A) 1.00 M B) 2.50 M C) 5.95 M D) 0.441 M
21) What is the mass of ethanol, C2H5OH, is required to produce 200. mL of 0.500 M solution?
A) 4.6g B) 6.91 g C) 92.1 M D) 13.8 g
22) Which one of the following substances is predicted to be soluble in water?
A) PbSO4 B) Mo(NO3)2 C) FeS D) Mg(OH)2
23) Which of the following are soluble? (i) BaSO4 (ii) AgBr (iii) Sr(NO3)2 (iv) Na2CO3
A) iv only B) iii only C) iii and iv D) i, iii, and iv
3. 24) Lithium and nitrogen react in a combination reaction to produce lithium nitride:
6Li (s) + N2 (g) 2Li3N (s)
How many moles of lithium nitride are produced when .450mol of lithium react in this fashion?
A) .225 B) .900 C) 1.35 D) .150 E).0750
25) Lithium and nitrogen react in a combination reaction to produce lithium nitride:
6Li (s) + N2 (g) 2Li3N (s)
In a particular experiment, 3.50g samples of each reagent are reacted. The theoretical yield of lithium nitride is _________g.
A) 2.93 B) 17.6 C) 5.85 D) 3.52 E) 8.70
26) Lithium and nitrogen react in a combination reaction to produce lithium nitride:
Li (s) + N2 (g) Li3N (s)
In a particular experiment, 3.50g samples of each reagent are reacted. What is the limiting reagent?
A) Li B) N2 C) Li3N D) no reagent is limiting
27) Lithium and nitrogen react in a combination reaction to produce lithium nitride:
Li (s) + N2 (g) Li3N (s)
In a particular experiment, 3.50g samples of each reagent are reacted. If the yield was 50%, the number of grams of lithium
nitride would be _________.
A) 2.93 B) 17.6 C) 5.85 D) 3.52
28) Atomic radius generally increases as we move _____a group and from _____ to _____ across a period.
A) down; right to left B) up; left to right C) down; left to right D) up; right to left
29) Which of the following correct list the five atoms in order of increase size (smallest to largest)?
A) O<Mg<S<F<Ba B) F<O<S<Mg<Ba C) Mg<F<O<S<Ba D) Ba<Mg<O<F<S
30). The ability of an atom in a molecule to attract electrons is best quantified by the _________________.
A) Ionization energy B) Valence Electron C) Molecular Weight D) Electronegativity
4. Answer Key (Exam 2 Chapter 3,4, & 7)
1. D
2. E
3. C
4. E
5. A
6. A
7. A
8. D
9. D
10. A
11. C
12. D
13. A
14. D
15. B
16. A
17. B
18. C
19. C
20. A
21. A
22. B
23. C
24. D
25. C
26. A
27. A
28. A
29. B
30. D
31.
