Page 194 - ICSE Chemistry 8

9 Carbon and Its Compounds

Learning Outcomes Key Concepts
Students will be able to
• Occurrence of Carbon
• explain the term allotropy.
• Compounds of Carbon
• describe diff erent allotropes of carbon.
• Chemical Properties of
• state the proper es of graphite and diamond.
Carbon
• prepare carbon dioxide in a laboratory.
• Allotropes of Carbon
• describe the uses of carbon dioxide.
• Carbon Dioxide
• demonstrate diff erent reac ons of carbon dioxide with lime water and • Carbon Monoxide
litmus solu ons.

Warm Up Activity
What is the symbol of the element carbon? _________________

What is the valency of carbon? _________________
Name any two compounds that consist of carbon.

_________________ _________________

Carbon is the sixth element in the periodic table with symbol C and atomic number 6. One atom of carbon
has 6 electrons and 6 protons. Its nucleus also has 6 neutrons. Thus, its mass number is 12. It is a non-
metal. The name carbon is derived from the La n word carbo which means coal. This is because carbon
is the main cons tuent of coal.
Organogens
A large number of things which we use in our daily life are made up Elements like hydrogen, oxygen,
of carbon and its compounds. Our food, clothes, fuel, paper, wood, carbon and nitrogen from which
plas cs, etc. are all carbon compounds. life has originated on earth are
called organogens.
Carbon is one of the organogens. It is also the major chemical
cons tuent of complex biomolecules (DNA and RNA) which control
the transmission of characters from one genera on to the next in living beings.

OCCURRENCE OF CARBON

Carbon is the fourth most abundant element in the universe.
In nature, carbon occurs in both free and combined states.

In free state, carbon occurs as diamond and graphite. Another naturally
occurring form of carbon called fullerene has been discovered recently. Fig. 9.1: Diamond

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