The number of carbon atoms per unit cell of diamond unit cell is:-

1. 4

2. 8

3. 6

4. 1

Hot and conc. ${\mathrm{HNO}}_3$ react with carbon to form:

1.  ${\mathrm{CO}}_2$

2.  $\mathrm{CO}$

3.  ${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{COOH}$

4.  ${\mathrm{NO}}_2+{\mathrm{CO}}_2$

The carbon of microphones used in public address systems is:

1.  graphite

2.  charcoal

3.  coke

4.  lamp black

The number of double bonds at alternate position in ${\mathrm{C}}_{60}$ molecule are

1.  20

2.  25

3.  30

4.  36

The incorrect statement regarding allotropes/allotropy is :

The incorrect statement regarding diamond and graphite is-