Index to Course Material Index to Section 4
1) Which would you expect to be the longer and why?
(a) the carbon-oxygen bond in a carbonyl group
(b) the carbon-oxygen bond in a tyrosine side-chain
2) Which amino acid residue has a charged state which is sensitive to
pH changes around neutral pH?
3) Why does ethanethiol have a lower boiling point (35C) than ethanol
(78C)?
4) In classical mechanics the internal energy of a molecule is made up
of two contributions. One is the potential energy.
What is the other?
5) In what manner does the van der Waals radius of an atom vary in going
along one
row of the periodic table from left to right?
6) How are force and potential energy related?
7) What is another name for 'relative permittivity'?
8) If two positively charged lysine residues are a given distance apart,
will the repulsion between them be greater in water or in methanol?
9) The Lennard-Jones potential
function contains two terms, one depending
on the sixth power of the distance between two atoms and the other depending
on the twelth power. Which term represents the repulsion of the electrons
when two atoms approach closely?
10) What is the approximate magnitude (in units of electrons) of the charge
on each hydrogen atom in a water molecule?
11) Approximately how long is a hydrogen-bond in water between the oxygen
acceptor and donor atoms? How does this distance compare with the
sum of the van der Waals radii of the two atoms?
12) Which type of interatomic force has the longest range?
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With thanks to David Moss
Last updated 14th May '96