c 1. The silicon atom in the SiH4 molecule is _____ hybridized and the H-Si-H bond angles are _____.

(a) sp2, 120° (b) sp2, 109.5° (c) sp3, 109.5°

(d) sp3, 120° (e) sp2, 90°

a 2. The PF5 molecule exists whereas NF5 does not. Which one of the following is the best explanation for this fact?

(a) Phosphorus atoms can undergo hybridization involving d orbitals, whereas

nitrogen atoms cannot.

(b) The first five ionization energies of nitrogen are too high but those of phosphorus are not.

(c) The electron affinity of nitrogen is too high.

(d) NF5 would be too polar to be stable.

(e) Simple P5+ ions exist but simple N5+ ions are too small to exist.

c 3. How many sigma(s) bonds and how many pi (p) bonds does the ethene molecule

contain?

(a) 4 s and 2 p (b) 5 s and 2 p (c) 5 s and 1 p

(d) 5 s and 0 p (e) 8 s and 2 p

c & d 4. Which molecule is incorrectly matched with the molecular geometry?

Molecule Molecular Geometry

(a) SeF6 octahedral

(b) CCl4 tetrahedral

(c) SO3 pyramidal

(d) SF4 tetrahedral

(e) SbH3 pyramidal

b 5. Which one of the following molecules is polar?

(a) AsF5 (b) PCl3 (c) CO2 (d) CF4 (e) SiH4

b 6. The total numbers of electrons in the _2p molecular orbitals of B2 is _____.

(a) 1 (b) 2 (c) 3 (d) 4 (e) zero

b 7. Which response lists only the molecules given below that are paramagnetic?

B2, C2, N2, N2^2-, C2²⁺

(a) B2 and N2 (b) B2, N2^2-, and C2²⁺ (c) N2 and N2^2-

(d) N2 and C2²⁺ (e) C2, N2^2-, and C2²⁺

a 8. According to the Arrhenius theory, which of the following is a base?

(a) KOH (b) H2O2 (c) NaCl (d) NH₃ (e) (OH)₂SO₂

e 9. Which cannot be both a Brønsted-Lowry acid and a Brønsted-Lowry base?

(a) H2O (b) HCO3– (c) H2PO4– (d) HPO42– (e) PO43–

c 10. Which one of the following statements is true?

CH3NH2 + H2O CH3NH3+ + OH–

methylamine water methylammonium ion hydroxide ion

(a) CH3NH2 is the conjugate base of H2O.

(b) CH3NH3+ is the conjugate base of CH3NH2.

(c) H2O is the conjugate acid of OH–.

(d) OH– is the conjugate acid of H2O.

(e) There are no conjugate acid-base pairs.

d 11. Which one of the following pairs of acids and conjugate bases is incorrectly labeled or incorrectly matched?

Acid Conjugate Base

(a) HClO2 ClO2–

(b) NH3 NH2–

(c) H2S HS–

(d) CO32– HCO3–

(e) HS– S2–

a 12. The following acids are listed in order of decreasing acid strength in water.

HI > HNO2 > CH3COOH > HClO > HCN

According to the Brønsted-Lowry theory, which one of the following anions is the

weakest base?

(a) I– (b) NO2– (c) CH3COO– (d) ClO– (e) CN–

a 13. Which one of the following pairs of acids is incorrectly listed?

Stronger Acid Weaker Acid

(a) HClO HClO2

(b) HNO3 HNO2

(c) H2SO4 H2SO3

(d) H2SO3 H2SeO3

(e) HClO4 HIO4

d 14. Which response gives all of the members of the following list that are acidic salts and

none that are not acidic salts?

KH2PO4, K2HPO4, K3PO4, NaHCO3, LiOH, LiH

(a) KH2PO4, K2HPO4, LiH (b) KH2PO4, NaHCO3, LiOH

(c) K3PO4, LiH (d) KH2PO4, K2HPO4, NaHCO3

(e) KH2PO4, K2HPO4, NaHCO3, LiH

a 15. Which one of the following reactions can be classified as a Lewis acid-base reaction but not as a Brønsted-Lowry acid-base reaction?

(a) Al(OH)3(s) + OH–(aq) � Al(OH)4–(aq)

(b) NH3(g) + H2O(l) � NH4+(aq) + OH–(aq)

(c) CH3COO–(aq) + H2O(l) � CH3COOH(aq) + OH–(aq)

(d) H+(g) + H–(g) � H2(g)

(e) Ca(OH)2(s) + 2HCl(g) � CaCl2(s) + 2H2O(l)

a 16. If 200. mL of 2.00 M H3PO4 solution is added to 600. mL of 2.00 M NaOH solution, the resulting solution will be ________ molar in Na3PO4.

(a) 0.500 (b) 0.667 (c) 0.800 (d) 1.00 (e) 0.100

b 17. Calculate the molarity of a NaOH solution if 35.42 mL of this NaOH solution is required

to titrate 0.7566 g of KHP, KC6H4(COO)(COOH). (MW of KHP = 204.2 g/mol)

(a) 0.05278 M (b) 0.1046 M (c) 0.2092 M

(d) 0.3128 M (e) 0.0105 M

c 18. What is the normality of a 0.0500 M H2SO4 solution?

(a) 0.0125 N (b) 0.0250 N (c) 0.100 N

(d) 0.0175 N (e) 0.0500 N

e 19. Iron(II) ions reduce Cr₂O₇^2- in acidic solution to chromium(III) ions and form ferric ions. Write the simplest balanced net ionic equation. What is the coefficient for H⁺?

(a) 24 (b) 18 (c) 9 (d) 12 (e)14

e 20. What is the molarity of a solution of FeSO4 if 25.06 mL of it reacts with 38.19 mL of 0.1214 M KMnO4?

MnO4– + 8H+ + 5Fe2+ � Mn2+ + 5Fe3+ + 4H2O

(a) 0.1854 M (b) 0.3992 M (c) 0.07985 M

(d) 0.4267 M (e) 0.9250 M

Draw the lewis dot structure for the noble gas compound xenon tetrafluoride, XeF4.

F F

\ /

: Xe :

/ \

F F

sp³d²

Octahedral

Square planar