As shown in figure when we take a small substance X a non metal in the spoon and heat it over a Bunsen burner flame, it starts burning to produce a gas. As soon as it starts burning we put it into a jar and cover it with a lid. After it stops burning, we remove the spoon and cover the jar with a lid. We then add a small amount of water inside the jar. We then shake the jar. a) Which is the substance X taken in the spoon? b) If you test the solution in the jar with red litmus paper, what would you observe? c) Can step ‘b’ give nature of solution? d) What does it indicate about the nature of the solution? Write a balanced chemical equation for the reaction of the gas produced with water.
Answers
Answer:
Many experiments require the application of heat. If an open flame is not to be hazardous, a gas burner is
needed to control the heat production. A common source of this heat is the heat energy released when a
fuel such as natural gas is burned in air.
Almost all laboratory burners used today are modifications of the original Bunsen bwner invented by the
German chemist Robert Bunsen. One of the more commonly used modifications is called a Tirri! burner.
Bunsen~s fundamental design is also widely used in domestic and indust.."i.al gas burners. To operate the
burner a combustible gas is allo·wed to flow rapidly from a jet into a mixing chamber (barrel); air
containing oxygen is drawn into the barrel through inlet holes due w a vacuum effect created by the
rapidly moving gas. At the top of the burner the gas · air mixture is combusted. The temperature may be
regulated by adjusting the ratio of gas to oxygen. With low amounts of oxygen, the flame is relatively cool
and is referred to as a luminous yellow flame. As more oxygen is mixed with the gas, the temperature of
the flame increases. A very hot flame is referred to as nonluminous and is characterized by a blue cone
surrounded by a larger yellowish envelope.
In this experiment the laboratory burner will be used to heat and soften glass tubing in order to
manipulate and bend the glass. For some manipulations it is desirable to heat a short section of the tubing
rather than a single point. This is accomplished by attaching a wing top {flame spreader) to the top of the
barrel. Other types of glassworking to be carried out are glass cutting and fire-polishing (smoothing out
sharp edges on glass by heating and softening).
The primary use of the lab bu..-ner in chemistry courses is to heat water, and if necessary keep the water
hot or warm.
The combustion of the gaseous mixture in the burner is a chemical reaction. Natw·al gas is principally the
chemical methane, a C-"Olorless, odorless gas. Gas companies reduce the potential danger of asphyxiation or
explosion, which could result from gas leakage, by adding, in small amounts, another chemical with a
pungent odor. Thus the presence of natural gas in the air from leaks or inadvertent open valves can
usually be detected before dangerous amounts escape. The chemical change which occurs when natural
gas is burned results in the formation of two other common chemical substances, carbon dioxide and water.
The overall reaction may be stated as follows:
When methane and oxygen gases are mixed and ignited, they react to form carbon dioxide gas, water
vapor, heat and light. The chemical reaction may also be described in the form of a word equation.
methane <gas)+ oxygen (gas) - carbon dioxide (gas)+ water (gas)+ energy
I
heat and light
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Procedure
A. Tirri! Burner
Examine the construction of vour burner and become familiar with the name and function
of each part. The burner may be disassembled into three parts, (see Figure