Page 33 - Curriculum Visions Dynamic Book

combustion: the special case of oxidisation of a substance where a considerable amount of heat and usually light are given out. Combustion is often referred to as “burning”.
+➡
 Chlorine gas is produced by the method shown on pages 10 and 11. Hydrogen gas (ignited) is introduced into a flask of chlorine gas. The flame becomes white. Notice also a white “mist” at the end of the tube. This is where the hydrogen chloride attracts moisture.
The hydrogen and chlorine react to produce hydrogen chloride gas, which then attracts water and forms a mist of acidic water droplets (hydrochloric acid).
Properties
Hydrogen chloride has a pungent smell. If any of the gas is inhaled it produces immediate, severe irritation of the nose and throat because it dissolves in the mucus membranes and immediately turns into hydrochloric acid.
In addition to the method of preparation shown in the pictures on these pages, hydrogen chloride can be made in the laboratory
by reacting concentrated sulphuric acid
on sodium chloride (see the equation on page 35).
Vinyl chloride is manufactured from acetylene and hydrogen chloride.
When polyvinyl chloride
is heated above 150°C, it decomposes, releasing about half its weight as hydrogen chloride gas.
EQUATION: Producing hydrogen chloride gas
Hydrogen+ chlorine ➪ hydrogen chloride gas
H2(g)
+ Cl2(g) ➪ 2HCl(g)
Hydrogen
Chlorine
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