Freie University of
Berlin's Chemistry department contains an index of amino acids that are linked
to a structure and a description of their physical properties. Learn more
about phenylalanine at this address: http://www.chemie.fu-berlin.de/chemistry/bio/aminoacid/phe_en.html.
Identify the hydrophilic
parts of phenylalanine.
Identify the hydrophobic
parts.
Suppose you had
a mole of phenylalanine in a liter of water and a mole of NaCl in a liter
of water, and the two components were separated by a semi-permeable membrane.
At equilibrium, will the water level be greater in the phenylalanine side
or the NaCl side? Or will they be equal?
If side A initially
had a 2 molar concentration of NaOH, what initial concentration of the
same compound would be needed to obtain the same result as shown in the
diagram at the bottom of the page?
Can a solution be
solid? If so, what would you define as the solvent?
Suppose you went
to the dentist to get a tooth filled, and after telling him your interest
in the chemical composition of the fillings, he told you it was composed
of 0.05 g of silver and 0.1 g of mercury. Find the molality of the solution.
Now, after having
your teeth filled, you see an assistant preparing a mouthwash of some
sort, pouring 2 moles of the cherry-flavored solute into a 250 mL bottle.
Calculate the molarity of the solution.
