CHEM 162, EXAM 1 2022 NEW PRACTICE EXAM QUESTIONS WITH
CORRECT ANSWERS
(1) (5 pts) Which one of these molecules has the same VSEPR structure as BeCl2 (circle one)?
NO2 SO2 ClI2+ NO2+ AlF2−
(2) (1 pts ea) For which molecule in each of the following pairs would you expect the stronger
intermolecular forces? Circle one in each problem.
(a) CH3CH2CH2CH2CH3 or (CH3)4C (b) (CH3)2C=O or (CH3)2CH-OH
(c) H2S or H2Se (d)
(e) CH3CH2CH3 or (CH3)2C=O
(3) TRUE/FALSE: Circle the correct ones (1 point each)
(a) bonds are usually stronger than bonds TRUE FALSE
(b) The bond in HCl is formed by mixing H2s and Cl2p orbitals TRUE FALSE
(c) Electrons in the same orbital must have opposite spins: TRUE FALSE
(d) C=C double bonds are longer than CC triple bonds: TRUE FALSE
(e) The total number of valence electrons in benzene molecular orbitals is 36: TRUE FALSE
(4) (5 pts) Which one of these molecules or ions has both the same molecular orbital diagram as BN−
and the same number of valence electrons? (circle one).
B2− NO+ CN O2+ C2+
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, Your name: ...................................................... Exam 1, CHEM 162, January 31, 2022
Quiz section: ...............
(5) (5 pts) Rank the following molecular molecular orbitals (a)-(d) in benzene from lowest energy to
highest:
(1) E(a) > E(b) > E(c) > E(d)
(a)
(2) E(b) > E(a) > E(d) > E(c)
(3) E(c) > E(a) = E(d) > E(b)
(4) E(d) > E(c) = E(a) > E(b) (b)
Circle the correct answer. (c)
(d)
(6) (1 point ea) Assign the hybridization at central atoms in the following molecules and ions:
PH4+ SiF5− ICl2− XeF4 AlF63–
sp3 sp3d sp3d sp3d2 sp3d2
(7) (5 pts) Using a MO energy-level diagram, would you expect N2 to have a higher or lower first
ionization energy (IE) than atomic nitrogen? Circle the correct answer.
IE(N2) > IE(N) IE(N2) < IE(N)
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CORRECT ANSWERS
(1) (5 pts) Which one of these molecules has the same VSEPR structure as BeCl2 (circle one)?
NO2 SO2 ClI2+ NO2+ AlF2−
(2) (1 pts ea) For which molecule in each of the following pairs would you expect the stronger
intermolecular forces? Circle one in each problem.
(a) CH3CH2CH2CH2CH3 or (CH3)4C (b) (CH3)2C=O or (CH3)2CH-OH
(c) H2S or H2Se (d)
(e) CH3CH2CH3 or (CH3)2C=O
(3) TRUE/FALSE: Circle the correct ones (1 point each)
(a) bonds are usually stronger than bonds TRUE FALSE
(b) The bond in HCl is formed by mixing H2s and Cl2p orbitals TRUE FALSE
(c) Electrons in the same orbital must have opposite spins: TRUE FALSE
(d) C=C double bonds are longer than CC triple bonds: TRUE FALSE
(e) The total number of valence electrons in benzene molecular orbitals is 36: TRUE FALSE
(4) (5 pts) Which one of these molecules or ions has both the same molecular orbital diagram as BN−
and the same number of valence electrons? (circle one).
B2− NO+ CN O2+ C2+
This study source was downloaded by 100000830772748 from CourseHero.com on 05-18-2022 20:12:56 GMT -05:00
https://www.coursehero.com/file/131984838/Midterm1-KEYpdf/
, Your name: ...................................................... Exam 1, CHEM 162, January 31, 2022
Quiz section: ...............
(5) (5 pts) Rank the following molecular molecular orbitals (a)-(d) in benzene from lowest energy to
highest:
(1) E(a) > E(b) > E(c) > E(d)
(a)
(2) E(b) > E(a) > E(d) > E(c)
(3) E(c) > E(a) = E(d) > E(b)
(4) E(d) > E(c) = E(a) > E(b) (b)
Circle the correct answer. (c)
(d)
(6) (1 point ea) Assign the hybridization at central atoms in the following molecules and ions:
PH4+ SiF5− ICl2− XeF4 AlF63–
sp3 sp3d sp3d sp3d2 sp3d2
(7) (5 pts) Using a MO energy-level diagram, would you expect N2 to have a higher or lower first
ionization energy (IE) than atomic nitrogen? Circle the correct answer.
IE(N2) > IE(N) IE(N2) < IE(N)
This study source was downloaded by 100000830772748 from CourseHero.com on 05-18-2022 20:12:56 GMT -05:00
https://www.coursehero.com/file/131984838/Midterm1-KEYpdf/
