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VIDEO 4 – SUPPORTING MATERIALS
Acetylene Production from Calcium Carbide
Course
SCH3U
SCH4U
Course
SCH4C
Curriculum Connections/Course and Expectations
Expectation
Teaching Notes
F2.5 determine, through inquiry, the As a follow up to the reaction seen in
molar volume or molar mass of a gas the video, acetylene can be collected
produced by a chemical reaction
by water displacement, using a known
(e.g., the molar volume of hydrogen
quantity of calcium carbide and the
gas from the reaction of magnesium
molar mass determined.
with hydrochloric acid) [PR, AI]
The purity of the calcium carbide can
then be determined by comparing the
theoretical and actual yields
C2.4 analyse, on the basis of inquiry, Students may vary the proportion of
various organic chemical reactions
the air to acetylene mixture in the test
(e.g., production of esters,
tube to determine its effect on the
polymerization, oxidation of
completeness of combustion.
alcohols, multiple bonds in an
organic compound, combustion
reactions, addition reactions) [PR,
AI]
Expectation
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]
C2.6 conduct an inquiry to identify
some of the products of the
combustion of a hydrocarbon and an
alcohol [PR, AI]
C2.7 conduct an inquiry to
synthesize a common organic
compound (e.g., produce an ester,
make soap) [PR]
Teaching Notes
Students may vary the proportion of
the air to acetylene mixture in the test
tube to determine its effect on the
completeness of combustion.
Fire Safety Knowledge and Skills Set
 Quantity of Materials
o Leave the stock container of calcium carbide in the storage room.
o The use of a small piece of calcium carbide minimizes the volume of acetylene gas
released and the resulting combustion hazard.
o Using a small quantity also minimizes the amount of acetylene released into the
atmosphere which helps to promote an attitude of environmental responsibility. It also
encourages students to use small quantities of chemicals in future investigations that they
may design.

Room Readiness
o Have protective eyewear available for students.
o Provide insulated gloves for handling hot glass.
o Have a bucket of sand available to extinguish unexpected flame.
 Student Readiness
o Caution students to place their reaction mixture in the fume hood if it generates more
acetylene gas than is required. This prevents acetylene gas from accumulating in the air
of the classroom.
o Remind students that the solution remaining in the test tube is calcium hydroxide, a skin
irritant. In case this solution comes in contact with the skin, the affected area should be
washed with plenty of cool tap water.

Suitable Heat Source
o A BBQ lighter or candle can be used to ignite the splint. A small Petri dish or watch
glass should be provided to collect melted candle wax.