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VIDEO 5 – SUPPORTING MATERIALS
Safely Synthesizing Esters
Curriculum Connections/Course and Expectations
Course Expectation
Teaching Notes
SBI3C B2.5 conduct biological tests to identify
Acetone can be used as a solvent to extract
biochemical compounds found in various fats from food samples, and allows for a
food samples (e.g., use a biuret solution
quantitative assessment of fat content. The
to test for proteins in samples of gelatin
brown paper bag test is a qualitative
and albumin), and compare the
alternative that does not require the use of
biochemical compounds found in each
flammable organic solvents.
food to those found in the others [PR, AI]
Course
SBI4U
SCH4U
SCH4C
Expectation
B2.4 conduct biological tests to identify
biochemical compounds found in various
food samples (e.g., use Benedict’s solution to
test for carbohydrates in food samples), and
compare the biochemical compounds found
in each food to those found in the others [PR,
AI, C]
C2.3 conduct a laboratory investigation of
the process of photosynthesis to identify the
products of the process, interpret the
qualitative observations, and display them in
an appropriate format [PR, AI,C]
D2.3 conduct an investigation to extract
DNA from a specimen of plant or animal
protein [PR]
B2.4 analyse, on the basis of inquiry, various
organic chemical reactions (e.g., production
of esters, polymerization, oxidation of
alcohols, multiple bonds in an organic
compound, combustion
reactions, addition reactions) [PR, AI]
C2.4 conduct an inquiry to determine the
physical and chemical properties of some
common organic compounds (e.g., solubility
[in polar and non-polar solvents],
conductivity, odour, combustibility) [PR, AI]
C2.5 conduct an inquiry to demonstrate
separation of a mixture of liquids by
distillation [PR]
C2.7 conduct an inquiry to synthesize a
common organic compound (e.g., produce an
ester, make soap) [PR]
Teaching Notes
Fats are a biochemical compound that can be
identified in food samples. Acetone can be
used as a solvent to extract fats from food
samples, and allows for a quantitative
assessment of fat content. The brown paper
bag test is a qualitative alternative that does
not require the use of flammable organic
solvents.
Warmed alcohol can be used to extract
chloroplasts from plant tissues, though with
obvious fire hazards.
Concentrated ethanol or 2-propanol (isopropyl
alcohol) is used to precipitate DNA from
solution during extractions.
Most organic compounds are flammable, and
many organic chemical reactions require the
addition of heat to get them started.
Limit the inquiry to the testing of properties
that do not require heat.
There are several different distillation
procedures that could fulfill this expectation;
the distillation of flammable substances is
only one option.
Most organic compounds are flammable, and
SNC4M
D2.2 plan and conduct chemical tests on a
variety of foods to determine their chemical
components (e.g., protein, starch, fats, lipids,
carbohydrates, vitamins) [IP, PR, AI]
many organic chemical reactions require the
addition of heat to get them started.
Acetone can be used as a solvent to extract
fats from food samples, and allows for a
quantitative assessment of fat content. The
brown paper bag test is a qualitative
alternative that does not require the use of
flammable organic solvents.
Fire Safety Knowledge and Skills Set:
 Choice of heat source
o A water bath is used to heat the methanol because it does not involve using an open flame
and it can be kept at a relatively low temperature.
 Student Readiness
o Review the appropriate handling procedures for concentrated acids with students prior to
the investigation. The teacher should plan to dispense the sulfuric acid catalyst.
 Room readiness
o The lab stations should be set up to minimize movement during the lab. Ensure that the
all of the necessary safety equipment is available and that the students are aware of the
risks associated with the reagents being used.
 Quantity of flammable and combustible materials
o Minimize the volume of methanol used. This reduces the amount of methanol vapour in
the air and the risk of accidental ignition of either the liquid methanol or its vapour.