1. accidentally dropped a jar of lentils and a jar of
sugar to the ground. Even though the jars did not break, the lids
came loose, and the lentils and sugar scattered all over the floor
and got mixed! I scooped up the lentil and sugar mix from the
ground and am now planning to separate them. Use the techniques you
have learnt in this experiment to design a procedure I should use
to separate the lentils from the sugar. (7 pts)
(Separation of a mixture using gravity and Buchner funnel
filtration and recrystallization lab)
2. How might the fractional distillation outlined in the lab
procedure be affected if a student failed to closely monitor the
thermometer and allowed the temperature to climb to around 111 °C
for a short time before removing the collection vial?
a)
The elevated temperature would drive a decomposition reaction
and substantially reduce the volume recovered.
b)
The water jacketed condenser would fail to condense the hotter
vapors and substantially reduce the volume recovered.
c)
Some toluene would contaminate the recovered ethyl acetate,
resulting in an apparent increase in volume but at the cost of
purity.
d)
The condensed ethyl acetate would occupy a larger volume at this
higher temperature, resulting in an increase in volume
recovered.
3. In this experiment, only the ethyl acetate is distilled. The
toluene is left behind in the distillation flask. This makes the
lab safer than distilling both of the compounds. What safety risk
is being minimized by completing the procedure in this manner?
a)
by only distilling the ethyl acetate, the distillation flask is
kept from distilling to dryness
b)
by only distilling the ethyl acetate, less hazards are faced
because ethyl acetate is not flammable, but toluene is
flammable.
c)
toluene is not flammable and thus is not capable of being
distilled
d)
all of the above are true