Introductory Chemistry
THE UNIVERSITY OF THE WEST INDIES
□ Supplemental/Summer School □
Examinations of December
/April/May □ /July □ 2009
Originating Campus:
Cave Hill
□
Mona
St. Augustine □
Mode:
On Campus
By Distance □
Semester l
Semester II
Course Code and Title: CHEM1901 - INTRODUCTORY CHEMISTRY A
Date:
Duration:
Time:
2
Hours.
Paper No: 1
Materials required:
Answer booklet:
Calculator:
(where applicable)
Multiple Choice answer sheets:
Programmable
□
□
numerical
□
Normal
Special
Not required
□
Non Programmable
□ 1-20 □ 1-100 □
alphabetical
Auxiliary/Other material(s) – Please specify:
CHEMISTRY ANSWER BOOKLET
Candidates are permitted to bring the following items to their desks:
Instructions to Candidates: This paper has
4
pages &
6
questions.
Candidates are reminded that the examiners shall take into account the proper use of the English Language in determining the mark for each response.
This paper has three (3) sections. You are required to answer FOUR questions in total.
Answer at least ONE question from EACH section.
Begin each question on a new page
The numbers in brackets on the right hand side of the paper are the marks allocated.
2
Section A
ATOMIC STRUCTURE
1. (a) The Lithium ion, Li2+, consists of a single electron moving about the Lithium nucleus.
(i) Calculate the gravitational force, and the electrostatic force on the electron, which is at a distance of one-third the Bohr radius from the nucleus.
( a o = 0.5292 Å, gravitation constant: G = 6.672 x 10-11 N m2 kg-2)
(8)
(ii) Comment on the magnitude and significance of the values obtained in (a)(i)
(4)
(b) The wavefunctions of hydrogen atoms, Ha and Hb, are ψa and ψb, respectively.
(i) Given that ψa and ψb can be positive or negative, write expressions for the possible wavefunctions for the interaction of Ha and Hb.
(4)
(ii) Determine the expressions for the intensities in each case in
□ Supplemental/Summer School □
Examinations of December
/April/May □ /July □ 2009
Originating Campus:
Cave Hill
□
Mona
St. Augustine □
Mode:
On Campus
By Distance □
Semester l
Semester II
Course Code and Title: CHEM1901 - INTRODUCTORY CHEMISTRY A
Date:
Duration:
Time:
2
Hours.
Paper No: 1
Materials required:
Answer booklet:
Calculator:
(where applicable)
Multiple Choice answer sheets:
Programmable
□
□
numerical
□
Normal
Special
Not required
□
Non Programmable
□ 1-20 □ 1-100 □
alphabetical
Auxiliary/Other material(s) – Please specify:
CHEMISTRY ANSWER BOOKLET
Candidates are permitted to bring the following items to their desks:
Instructions to Candidates: This paper has
4
pages &
6
questions.
Candidates are reminded that the examiners shall take into account the proper use of the English Language in determining the mark for each response.
This paper has three (3) sections. You are required to answer FOUR questions in total.
Answer at least ONE question from EACH section.
Begin each question on a new page
The numbers in brackets on the right hand side of the paper are the marks allocated.
2
Section A
ATOMIC STRUCTURE
1. (a) The Lithium ion, Li2+, consists of a single electron moving about the Lithium nucleus.
(i) Calculate the gravitational force, and the electrostatic force on the electron, which is at a distance of one-third the Bohr radius from the nucleus.
( a o = 0.5292 Å, gravitation constant: G = 6.672 x 10-11 N m2 kg-2)
(8)
(ii) Comment on the magnitude and significance of the values obtained in (a)(i)
(4)
(b) The wavefunctions of hydrogen atoms, Ha and Hb, are ψa and ψb, respectively.
(i) Given that ψa and ψb can be positive or negative, write expressions for the possible wavefunctions for the interaction of Ha and Hb.
(4)
(ii) Determine the expressions for the intensities in each case in