NAME:___________________________ Section:_____ Student Number:__________________
Spring 2020 Chemistry 2000 Midterm #1A ____/65 marks
INSTRUCTIONS: 1) Please read over the test carefully before beginning. You should have 8 pages
of questions, a blank “overflow” page and a periodic table page.
2) If your work is not legible, it will be given a mark of zero.
3) Marks will be deducted for incorrect information added to an otherwise correct
answer.
4) Calculators are not permitted.
5) You have 90 minutes to complete this test.
Confidentiality Agreement:
I agree not to discuss (or in any other way divulge) the contents of this exam until after 8:30 pm Mountain
Time on Tuesday, February 11th, 2020. I understand that breaking this agreement would constitute
academic misconduct, a serious offense with serious consequences. The minimum punishment would be
a mark of 0/65 on this exam and removal of the “overwrite midterm mark with final exam mark” option
for my grade in this course; the maximum punishment would include expulsion from this university.
Signature: ___________________________ Date: _____________________________
Course: CHEM 2000 (General Chemistry II)
Semester: Spring 2020
The University of Lethbridge
Question Breakdown
Q1 / 16
Q2 /7
Q3 / 20
Q4 / 16
Q5 /6
Total / 65
, NAME:___________________________ Section:_____ Student Number:__________________
1. [16 marks]
(a) Develop the valence molecular orbital energy level diagram for 𝐵𝐵2. [7 marks]
Your diagram must include:
• labeled molecular orbital energy levels (you don’t need to draw pictures of the MOs)
• identification of each molecular orbital as bonding, nonbonding or antibonding
• electrons in the appropriate molecular orbitals
(b) Calculate the bond order for 𝐵𝐵2 [1 mark]
1 1
bond order = 2 (bonding − antibonding) = 2 (4 − 2) = 1
(c) Identify and sketch the HOMO and LUMO of 𝐵𝐵2. [4 marks]
HOMO: 1π LUMO: 3σ
Technically, the 1π orbitals are SOMOs (Singly Occupied Molecular Orbitals), but they are the Highest
energy Occupied Molecular Orbitals, and 3σ is the Lowest energy completely Unoccupied Molecular
Orbital.
Spring 2020 Chemistry 2000 Midterm #1A ____/65 marks
INSTRUCTIONS: 1) Please read over the test carefully before beginning. You should have 8 pages
of questions, a blank “overflow” page and a periodic table page.
2) If your work is not legible, it will be given a mark of zero.
3) Marks will be deducted for incorrect information added to an otherwise correct
answer.
4) Calculators are not permitted.
5) You have 90 minutes to complete this test.
Confidentiality Agreement:
I agree not to discuss (or in any other way divulge) the contents of this exam until after 8:30 pm Mountain
Time on Tuesday, February 11th, 2020. I understand that breaking this agreement would constitute
academic misconduct, a serious offense with serious consequences. The minimum punishment would be
a mark of 0/65 on this exam and removal of the “overwrite midterm mark with final exam mark” option
for my grade in this course; the maximum punishment would include expulsion from this university.
Signature: ___________________________ Date: _____________________________
Course: CHEM 2000 (General Chemistry II)
Semester: Spring 2020
The University of Lethbridge
Question Breakdown
Q1 / 16
Q2 /7
Q3 / 20
Q4 / 16
Q5 /6
Total / 65
, NAME:___________________________ Section:_____ Student Number:__________________
1. [16 marks]
(a) Develop the valence molecular orbital energy level diagram for 𝐵𝐵2. [7 marks]
Your diagram must include:
• labeled molecular orbital energy levels (you don’t need to draw pictures of the MOs)
• identification of each molecular orbital as bonding, nonbonding or antibonding
• electrons in the appropriate molecular orbitals
(b) Calculate the bond order for 𝐵𝐵2 [1 mark]
1 1
bond order = 2 (bonding − antibonding) = 2 (4 − 2) = 1
(c) Identify and sketch the HOMO and LUMO of 𝐵𝐵2. [4 marks]
HOMO: 1π LUMO: 3σ
Technically, the 1π orbitals are SOMOs (Singly Occupied Molecular Orbitals), but they are the Highest
energy Occupied Molecular Orbitals, and 3σ is the Lowest energy completely Unoccupied Molecular
Orbital.
