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प्रश्न
Explain the following.
Diamond, graphite and fullerenes are crystalline forms of carbon.
उत्तर
- A crystalline form of carbon has a regular and definite arrangement of atoms.
- In a diamond, each carbon atom is linked to four other carbon atoms by covalent bonds. Therefore, a diamond has a tetragonal three-dimensional structure. Hence a regular and definite structure of atoms is found in diamond.
- In graphite, each carbon atom is bonded to three other carbon atoms in such a way that a hexagonal layered structure is formed. Thus, the regular arrangement of atoms in graphite is in layers.
- In fullerene, C60 atoms are joined to each other in pentagonal and hexagonal arrangements. As a result, the structure of fullerene is like a football. The molecules of fullerene are found in the form of buckyballs and buckytubes.
- Since diamond, graphite and fullerene have definite shapes, sharp edges and plane surfaces, they are in crystalline form. Hence, Diamond, graphite and fullerenes are crystalline forms of carbon.
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संबंधित प्रश्न
Fill in the blank.
The tendency of an element to exist in two or more forms but in the same physical state is called ................
______ and ______ are the two major crystalline allotropes of carbon.
Define the Following Term:
Catenation
State the term:
Substances whose atoms or molecules are arranged in a definite pattern.
State the term:
Different forms of an element found in the same physical state.
Name the following:
The third crystalline form of carbon.
Answer the following question
Why is graphite a good conductor of electricity but not diamond?
Give two uses of graphite.
Fill in the blank
.............is formed when charcoal is burnt in a limited supply of air.
How is wood charcoal made locally? What other substances are formed in the process.
Name four types of coal with percentage of carbon present in each,with uses.
Name the products formed when:
diamond is burnt in air at 900°C.
Name the products formed when:
graphite is subjected to high pressure and 3000°C temperature.
Tick the most appropriate answer.
Fuel gases like water gas and producer gas are manufactured from
a. bone charcoal
b. wood charcoal
c. coke
d. none of these
Why does diamond sparkle?
How is wood charcoal a better fuel than wood?
Define the term ‘allotropy’. Give a reason why carbon exhibits allotropy.
‘Wood charcoal – an amorphous aliotrope of carbon reduces heated metallic oxides to metals.’ Give a balanced equation to support the statement.
Name the following:
An amorphous allotrope of carbon which floats on water.
The amorphous allotropic carbon is used for making electrodes in dry cell ______.
