BIOL 304 EXAM 3 | QUESTIONS AND
ANSWERS | 2026 UPDATE | WITH
COMPLETE SOLUTIONS
solubility of monosaccharides vs. polysaccharides - ANSWER>monosaccharides are water soluble but
polysaccharides are insoluble in cold water and must be heated in order to be partially soluble
are carbohydrates optically active - ANSWER>yes because of the presence of chiral carbon centers (asymmetric
atom)
what does it mean to be optically active - ANSWER>ability of the compound to rotate plane polarized light to the
right or left
difference between D and L and d and l - ANSWER>D and L refers to configuration of stereochemistry of the
molecule; d and l refers to optical rotation of plane polarized light
what is the biot law - ANSWER>the extent of polarization is related to the concentration of the optically active
molecules in the solution
, what is the Biot law equation - ANSWER>[α]t λ=α/(l*c)
what is [α]Tλ - ANSWER>optical activity at a defined temperature T and wavelength
what are the other variables in biot's law - ANSWER>α=optical rotation (measured angle of rotation)
l=optical pathlength in dm
c=concentration in g/ml
what is true of Biot's law - ANSWER>it is additive; meaning that the optical activity of the whole solution is equal to
the optical activity of A + B...+C
what is the most important chemical property of carbohydrates - ANSWER>they have the reducing power to reduce
copper II ion in an alkaline solution to CU I
what physical change occurs during the reduction of copper - ANSWER>color changes from blue to brick red
ANSWERS | 2026 UPDATE | WITH
COMPLETE SOLUTIONS
solubility of monosaccharides vs. polysaccharides - ANSWER>monosaccharides are water soluble but
polysaccharides are insoluble in cold water and must be heated in order to be partially soluble
are carbohydrates optically active - ANSWER>yes because of the presence of chiral carbon centers (asymmetric
atom)
what does it mean to be optically active - ANSWER>ability of the compound to rotate plane polarized light to the
right or left
difference between D and L and d and l - ANSWER>D and L refers to configuration of stereochemistry of the
molecule; d and l refers to optical rotation of plane polarized light
what is the biot law - ANSWER>the extent of polarization is related to the concentration of the optically active
molecules in the solution
, what is the Biot law equation - ANSWER>[α]t λ=α/(l*c)
what is [α]Tλ - ANSWER>optical activity at a defined temperature T and wavelength
what are the other variables in biot's law - ANSWER>α=optical rotation (measured angle of rotation)
l=optical pathlength in dm
c=concentration in g/ml
what is true of Biot's law - ANSWER>it is additive; meaning that the optical activity of the whole solution is equal to
the optical activity of A + B...+C
what is the most important chemical property of carbohydrates - ANSWER>they have the reducing power to reduce
copper II ion in an alkaline solution to CU I
what physical change occurs during the reduction of copper - ANSWER>color changes from blue to brick red
