OXIDES OF CARBON

The graphite crystal is ...................... in shape

• Octagonal

• Hexagonal

• Diagonal

• Decimal

Answer explanation

The graphite crystal is hexagonal in shape. The carbon atoms in graphite form flat layers.

The following are occurences of carbon EXCEPT

• It does not ocur naturally as diamond and graphite

• It occurs in an impure form as coal

• It occurs in the atmosphere

• It occurs in the combined state as petroleum, wood and natural gases

Answer explanation

Occurences of Carbon includethe following: naturally as graphite and diamond

in combined state as Petroleum, wood and natural gases

in minerals such as limestone and Dolomite

in the atmosphere as carbon (IV) oxide

as essentials constituent of all forms of plants and animals.

One of these is an allotropic form of Carbon................

• Octahedral allotrope

• Monoclinic alotrope

• Crystalline allotrope

• Rhombic allotrope

Answer explanation

Carbon exists in several allotropic forms:

Crystaline allotropes: Diamond and graphite

Non-crystalline/ Amorphous carbon: coal, lampblack, and soot.

Properties of Diamond include the following EXCEPT

• Hard ans strong

• high density

• Resistant to chemical

• Highly reflective

Diamond is NOT used ffor the following............

• Drilling

• Sharpening

• Jewellery

• Softening

Answer explanation

Diamond is used for the following

drilling, sharpning hard tools, cutting glass and metals, pivot support, and making jewellery,

Graphite is NOT...........

• Soft and slippery

• Less dense and prone to chemical attack

• A poor conductor of electricity

• Inert and used to absorb radiations

Answer explanation

Graphite is:

Sofft and slippery

Dense and prone to chemical attack

A good conductor of electricity

Inert and used to absorb radiations in nuclear stations

Graphite is produced industrially by ...............

• mixing carbon in an electric furnace

• heating carbon in an electric furnace

• heating coke in an electric furnace

• mixing coke in an electric furnace

Answer explanation

Graphite is produced inddustrially by heating coke in an electric furnace to a very high temperature for abut 20 to 30 hours

What is Allotropy?

Describe briefly the industrial prpearation of Graphite

List the Amorphous Alotropes of Carbon