experiment: colligative properties
Water cannot be used as the solvent for this experiment. For
what types of molecular substances - give specific examples - could
water be used as a suitable solvent to determine a molecular
weight?
Can water be used to determine the formula weights of all ionic
compounds? What are the limitations, if any?
Why does the slope of the mixed solution continue to decrease
rather than reaching a plateau like that observed for the pure
liquid? Hint:...
In this experiment column chromatography, two different elution
solvent systems were used. Why?
If their order had been reversed (i.e., 20:80 EtOAc–Hex was used
first), how would the separation of the fractions have changed?
In this experiment column chromatography, two different elution
solvent systems were used. Why?
If their order had been reversed (i.e., 20:80 EtOAc–Hex was used
first), how would the separation of the fractions have changed?
Why do we call water the universal solvent? All life, as we know
it, needs water. What is the importance, relative to water being a
universal solvent, to living systems?
Water is a good solvent, but drugs are often bad solutes.
a) Explain why drugs are bad solutes and why water is not a good
solvent for all drugs.
b) Discuss TWO (2) techniques that can be used to improve the
solubility of drugs for the preparation of oral liquid
formulations.
An anion-exchange resin can be used instead of the
cation-exchange resin in this experiment to separate the three
amino acids in the known mixture. What changes to experimental
protocol are required to achieve complete resolution? Support your
response with an explanation. (HINT: consider pH).
You have been provided a mixture containing four amino acids
(Glu, His, Pro and Lys) to be separated by ion-exchange
chromatography using a Dowex 50 cation-exchange, prepared in a
loading buffer at pH 2.0. The following...
Experiment : Determination of Water Hardness Using a
Titrator
EDTA 0.010 M used for the experiment
the titrator with 7–9 mL of distilled water. = I used
9mL
the graduated cylinder to measure exactly 10 mL of tap water
from your faucet.
Add 5 drops of pH 10 buffer solution to the 10 mL of tap water
in the beaker
Dip approximately 10 mm of a toothpick into the distilled water.
Then, while toothpick is still damp, dip the toothpick...