TOPIC 3: HEAT SOURCES AND FLAMES
chemical reactions require heat to proceed. It is therefore important
to have sources of heat in a laboratory for heating various reacting
substances. Sources of heat in a chemistry laboratory may include Bunsen
burner, candle, spirit burner, kerosene burner (stove), tin lamp (kibatari) and charcoal burner. These are burners commonly used in most school laboratories.
Different Heat Sources which can be Used in a Chemistry Laboratory
Name different heat sources which can be used in a chemistry laboratory
Bunsen burner is the best of all burners because it is convenient to
handle. Another advantage of the Bunsen burner is that it produces a hot
flame whose temperature is approximately 1000°C. The temperature can be
adjusted easily to produce a non-luminous flame, which does not produce
spirit burner can also produce a soot-free flame. But the flame is not
hot enough to effect (produce) some chemical reactions. Apart from that,
the burner is filled with spirit, a substance that is highly flammable.
candle can only be used where a chemical reaction does not require much
heat. Its disadvantage is that it produces a lot of soot. The other
burners, though not commonly used, are an electric heater and a gas
electric heater uses electricity. The gas burner uses a liquefied gas.
The disadvantage of an electric burner is that it cannot be used in
rural areas where there is no electricity.
A kerosene burner (stove), also called jiko la mchina
in Swahili, if well adjusted can produce a flame hot enough to heat
many substances in the laboratory. It is fulled with kerosene, a fuel
that is convenient to carry and store. This fuel does not catch fire
easily as compared to spirit and it is affordable
can conveniently be used by schools in the most remote areas where
there is no electricity. If too much heating is required, wire gauze
should be placed on top of the burner. This will enable reduce soot and
increase the heating temperatures to about 1000°C or more.
Kerosene burner (stove)
charcoal burner can also be used in remove areas. In case the kerosene
burner is not available, for one reason or another, a charcoal burner
can be the best alternative.
The red-hot charcoal on the burner is almost soot-free. It can produce high temperature sufficient to carry out many reactions.
A tin lamp (kibatari), though it produces a lot of soot, can also be used as a burner in a laboratory, especially in remote areas.
However, the heat it produces is not hot enough to initiate some reactions.
The Functioning of a Bunsen Burner
Explain the functioning of a bunsen burner
all the burners we have discussed so far, a Bunsen burner is the mostly
used. Therefore, we are going to discuss about the functioning of the
Bunsen burner in more detail. As the name suggests, this burner was
invented by a German scientist called Robert Bunsen, so it was named
after his name as a Bunsen burner. The burner uses coal gas, which burns
with a hot and non-luminous flame when the air holes are open. This is a
kind of flame we normally use in the laboratory.