Allostropoes

Question 1

What are allotropes?

Answer 1

Different form of an element in the same physical state
eg.Oxygen and ozone

Question 2

What are allotropes of carbon?

Answer 2

1)Diamond
2)Graphite
3)Fullerene
3)Graphene

Question 3

How carbon are bonded in diamond?

Answer 3

one carbon atom is covalently bonded to other 4 carbon atoms.

Question 4

What is the hybridization of diamond?

Answer 4

sp3 hybridization (4 electron domain)

Question 5

Structure of carbon atom in diamond

Answer 5

one carbon atom is covalently bonded to other 4 carbon atoms in tetrahedral shape. (109.5 degree)

Question 6

How carbon are bonded in graphite?

Answer 6

one carbon atom is covalently bonded to other 3 carbon atoms.

Question 7

What is the hybridization of graphite?

Answer 7

sp2 hybridization (4 electron domain)

Question 8

Structure of carbon atom in graphite

Answer 8

one carbon atom is covalently bonded to other 3 carbon atoms in trigonal planar shape.(120 degree)
Contains delocalized electrons because of the movement of electrons in pi bond of the double bonds.

Question 9

Graphite bonds

Answer 9

One carbon atom is attached to other 3 carbon atoms.Therefore there must be a double bond in the structure of graphite.(Double bond=1 sigma bond & 1 pi bond)
The electrons in the pi bond are loosely attached and can move freely.

Question 10

Structure of graphite

Answer 10

Each graphite exist as hexagon structure and arranged in layers by London dispersion force.

Question 11

What are giant covalent molcules?

Answer 11

a molecule that contain regular repeated patteren that are covalently bonded

Question 12

Among carbon allotrope,which are giant covalent molecule?

Answer 12

Diamond, Graphite & Graphene

Question 13

Why fullerence is not giant covalent?

Answer 13

Bcus it contains both 6 carbon rings and 5 carbon rings not only one repeated unit.

Question 14

How many carbon atoms are in fullerence?

Answer 14

60 carbons

Question 15

Do fullerenes & Graphene can conduct electricity?

Answer 15

Yes
Both contains delocalized electrons (bcus of the double bonds)

Question 16

What is graphene?

Answer 16

A single layer of graphite

Question 17

Why diamond can’t conduct electricity?

Answer 17

Bcus there is no delocalized electrons in the diamon (bonded by single bonds)

Question 18

The layers of graphite are fixed.True or False?

Answer 18

False
The layers can slide each other b/c they are held together by london dispersion force.

Question 19

Shape of Fullerene

Answer 19

Sphere shape (12 pentagons & 20 hexagons)

Question 20

Shape of graphene

Answer 20

Honeycomb shape

Question 21

All of the carbon allotropes can conduct electricity.True or False?

Answer 21

False
Diamond cannot conduct electricity

Question 22

All of the carbon allotropes are giant covalent structures.True or False?

Answer 22

False
Fullerene is not giant covalent.

Question 23

All of the carbon allotropes can conduct heat.True or False?

Answer 23

True
Diamond is vvery efficient thermal conductor.

Question 24

All of the carbon allotropes have very high melting point.True or False?

Answer 24

False
Fullerene have low melting point

Question 25

Physical apperance of graphite

Answer 25

Soft and slippery Brittle

Question 26

Physical apperance of Diamond

Answer 26

Hardest Brittle

Question 27

Physical apperance of Fullerene

Answer 27

Very light and strong

Question 28

Physical apperance of graphene

Answer 28

Thinnest but strongest Flexible

Question 29

Uses of Graphite

Answer 29

Pencils ,electrode rods

Question 30

Uses of Diamond

Answer 30

Jewellery, glass grinding

Question 31

Uses of fullerene

Answer 31

Nanotubes

Question 32

Uses of Graphene

Answer 32

TEM & touch screen

Question 33

What is silicon dioxide?

Answer 33

Giant covalent structure known as silica or quartz

Question 34

Arrangement of atoms in silicon dioxide

Answer 34

One silicon atoms is attached to 4 oxygen atoms in tetrahedral shape (109.5 degree)

Question 35

What is the hybridization of silicon dioxide?

Answer 35

sp3 hybridization (4 electron domains)

Question 36

Is silicon dioxide giant covalent?

Answer 36

Yes

Question 37

Properties of silicon dioxide

Answer 37

Strong Insoluble in water High melting point Non-conductor

Question 38

Properties of giant covalent structure

Answer 38

1) high melting point & boiling point 2) Insoluble 3) Cannot conduct electricity (except graphite & graphene)

Question 39

All of th giant covalent structure cannot conduct electricity.True or False?

Answer 39

False Graphite and Graphene can conduct electricity.