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Topics in organic chemistry end semester past papers

Current Topics in organic chem
UNIVERSITY OF EMBU
2017/2018 ACADEMIC YEAR
SECOND SEMESTER EXAMINATIONS

FIRST YEAR EXAMINATION FOR THE DEGREE OF MASTER OF SCIENCE IN

CHEMISTRY

SCH 509: CURRENT TOPICS IN INORGANIC CHEMISTRY
DATE: APRIL 6, 2018 TIME: 2:00-5:00PM

INSTRUCTIONS:
Answer question ONE and any other TWO questions
QUESTION ONE (30 MARKS)
a) Explain the meaning of the following terms:- (8 marks)
i) Nanoscience
ii) Nanotechnology
iii) Self-assembly
iv) Heavy metal
b) Describe the three basic steps in nanoparticle formation from solution. (6 marks)

c) Cisplatin is perhaps the best known example of a clinically used small molecule metal-
containing cancer chemotherapeutic agent. Draw the structure of cisplatin and discuss its

limitations.
d) Discuss briefly any two features common to self-assembly processes.

(6 marks)
(4 marks)
e) Briefly explain three conditions that an element must satisfy in order to be categorized as an
essential an element. (6 marks)
QUESTION TWO (20 MARKS>

a) fag~lain with examples the bottom-up and top-down techniques. What are their merits and ====–~-
demerits? (10 marks)
b) Explain five major areas of technology where nanotechnology can play important roles.
( l 0 marks)

QUESTION THR]i:E (20 MARK~}
a) Discuss the hazards of heavy metal contamination. (I 0 marks)
b) Chelation therapy has the intent of scavenging toxic metal ions from the organism, or of
attenuating their toxicity by converting them in less toxic compounds, or of transferring them
from the site where they exert their toxic action to a compartment where this cannot be
executed. Briefly, discuss five essential prope1ties of a chelating agent, based on chemical and
biomedical considerations. (I 0 marks)
QUESTION OUR (20 MARKS)
a) Describe the chemical and physical vapor deposition (CVD and PYO) methods for synthesis
of nanomaterials. (I 0 marks)
b) Discuss the benefits, drawbacks and newer strategies of chelation therapy. (I 0 marks)


QUESTION FIVE (20 MARKS)
a) Describe the principles and processes of Scanning tunneling microscopy (STM) and atomic
force microscopy (AFM) methods for characterization of nanomaterials. ( 10 marks)
b) Distinguish between scanning electron microscopy (SEM) and (transmission electron
microscopy) TEM. What is the principal difference in sample preparation and detection?
(10 marks)

–END–