Which of the following arrangements shows the schematic alignment of magnetic moments of antiferromagnetic substances? 

1. $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\uparrow }$

2. $\overline{)\downarrow }$ $\overline{)\downarrow }$ $\overline{)\downarrow }$ $\overline{)\downarrow }$ $\overline{)\downarrow }$ $\overline{)\downarrow }$

3. $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\downarrow }$ $\overline{)\uparrow }$ $\overline{)\uparrow }$ $\overline{)\downarrow }$

4. $\overline{)\uparrow }$ $\overline{)\downarrow }$ $\overline{)\uparrow }$ $\overline{)\downarrow }$ $\overline{)\uparrow }$ $\overline{)\downarrow }$

Graphite is a good conductor of electricity due to the presence of ......... .

(1) Lone pair of electrons.

(2) Free valence electrons.

(3) Cations.

(4) Anions.

Which of the following oxides shows electrical properties like metals?

1.  SiO₂

2.  MgO

3.  SO₂ (s)

4.  CrO₂

The incorrect statement among the following is:

A ferromagnetic substance becomes a permanent magnet when it is placed in a magnetic field because:

The value of the magnetic moment is zero in the case of antiferromagnetic substances because the domains -

The correct choice among the given is -

1. (I, II)

2. (II, III)

3. (III, IV)

4. (I, IV)

Consider the following statements about semiconductors.

1. I and II

2. II and III

3. III and IV

4. I and IV