The Last Pages of Each Examination Has Reference Sheets

Chemistry 106: General Chemistry Syracuse University Project Advance Exam #3, Fall 2001

Name Date

The last pages of each examination has reference sheets

(1) A double bond is

(a) stronger and shorter than a triple bond (b) weaker and longer than a single bond (c) weaker and shorter than a triple bond (d) stronger and longer than a single bond (e) stronger and shorter than a single bond

(2) The oxidation number of nitrogen in BF3 is

(a) +2 (b) -2 (c) +1 (d) -1 (e) +3

(3) For the Lewis structure, the formal charges on N, N, and O, respectively (from left to right in the structure) are

(a) -1, +2, -1 (b) -1, +1, 0 (c) 0, 0, 0 (d) 0, +1, -1 (e) -2, +2, 0

(4) Which chloride should exhibit the most covalent (least ionic) type of bonding?

(a) AlCl3 (b) PCl3 (c) KCl (d) MgCl2 (e) NaCl

(5) Which species has more than eight electrons around the central atom?

CHE 106 1 Fall 2001 Exam Questions (a) BF3 - (b) BF4 (c) BrF3 (d) NF3 (e) PF3

(6) The electron-pair geometry (parent structure) and molecular geometry of bromine trifluoride are, respectively,

(a) trigonal planar, trigonal planar (b) tetrahedral, trigonal pyramidal (c) trigonal bipyramidal, T-shaped (d) octahedral, trigonal planar (e) trigonal bipyramidal, trigonal bipyramidal

(7) The approximate adjacent F-Xe-F bond angle in XeF4 is

(a) 90° (b) 109° (c) 120° (d) 180° (e) 104.5°

(8) The TOTAL bonding in acetylene (C2H2) consists of

(a) one  and one  bond (b) two  and one  bond (c) two  and two  bond (d) three  and two  bond (e) three  and no  bond

(9) Using molecular Orbital Theory, determine the bond order of the O2 molecule

(a) 0 (b) 1 (c) 1.5 (d) 2 (e) 2.5

(10) Generally, a molecule in which the central atom is sp3d2 hybridized will have electron-pair geometry

(a) octahedral (b) linear (c) trigonal planar (d) trigonal bipyramidal (e) tetrahedral (11) The molecules shown below all have the general formula AB3. Which of the following correctly identifies the molecular shape of the corresponding molecule? BCl3 NH3 ICl3 (a) T-shaped trigonal planar trigonal pyramidal CHE 106 2 Fall 2001 Exam Questions (b) trigonal planar trigonal pyramidal T-shaped (c) trigonal pyramidal trigonal planar T-shaped (d) trigonal planar trigonal planar trigonal planar (e) T-shaped trigonal pyramidal trigonal planar

(12) A molecular orbital that is symmetrical for rotation about the internuclear axis is called

(a) a bonding orbital (b) an anti-bonding orbital (c) a pi orbital (d) a sigma orbital (e) a nonbonding orbital

(13) If a bond has a bond order of three, this means that

(a) the bond has exactly the same number of bonding electrons as antibonding electrons (b) the bond has 3 more bonding electrons than it has antibonding electrons (c) the bond has 3 more antibonding electrons than it has bonding electrons (d) the bond must have considerable ionic character (e) the bond has 6 more bonding electrons than it has antibonding electrons

(14) When 2.34 L of air is released from an automobile tire at 37.5 psi (pounds per square inch), the volume it occupies at 14.7 psi is

(a) 0.427 L (b) 0.917 L (c) 2.34 L (d) 5.97 L (e) none of these

(15) In the following reaction, 81.2 mL of O2(g) were collected over water at 23° C and a barometric pressure of 751 torr. What is the mass of Ag2O3(s) that was decomposed? (Vapor pressure of water at 23° C is 21.2 torr; molar mass Ag2O = 231.7 g).

2 Ag2O(s) ------> 4 Ag(s) + O2(g)

(a) 0.00321 g (b) 0.00330 g (c) 1.49 g (d) 0.75 g (e) none of these

(16) A gas sample containing 0.283 mol of O2 and 0.942 mol of N2 at –17.0° C fills a volume of 25.9 L at a pressure of

(a) 0.230 atm (b) 0.765 atm (c) 0.994 atm CHE 106 3 Fall 2001 Exam Questions (d) 1.13 atm (e) none of these

(17) Cylinders of compressed gases are often filled by mass. Adding enough acetylene, C2H2, to a 385 L cylinder to increase the pressure by 18.5 atm at 21.3 ° C would increase the mass of the cylinder by

(a) 3.84 kg (b) 7.67 kg (c) 53.1 kg (d) 106 kg (e) none of these

(18) For the molecule shown

(a) The hybridization for C is sp3 (b) The hybridization for N is sp2 (c) The hybridization for O is sp2 (d) N is not hybridized (e) The hybridization for C is sp2

(19) What is the molar mass of a gas if 1.00 L of it at 0oC and 1.00 atm pressure has a mass of 2.86 g?

(a) 22.4 g/mole (b) 58.7 g/mole (c) 64.1 g/mole (d) 69.9 g/mole (e) 80.2 g/mole

(20) Under what set of conditions would sulfur dioxide, SO2 (g), be expected to deviate the most from ideal gas behavior?

(a) high temperature and low pressure (b) low temperature and high pressure (c) high temperature and high pressure (d) low temperature and low pressure (e) standard temperature and pressure

CHE 106 4 Fall 2001 Exam Questions