Sodium

Magnesium

Calcium

Aluminium

The properties of elements are the periodic functions of their atomic radii.

The properties of elements are the periodic functions of their atomic numbers.

The properties of elements are the periodic functions of their atomic masses.

The properties of elements are the periodic functions of their number of elements.

Hydrogen has three isotopes.

Hydrogen may be prepared by the action of hot 20% NaOH on silicon.

Nascent hydrogen reduces ferric chloride to ferrous chloride.

Hydrogen gas is corrosive in nature.

exhibit chemical inertness

react only with carbon compounds

are very reactive

cannot produce oxygen

size of the orbital

angular momentum of an electron

shape of the orbital

spin of the electron

• 2

• 2

• 1

• 1

H > F > Cl > Br > I

H < F < Cl < Br < I

F < Br < H < Cl < I

Br < Cl < H < F < I

Because atomic radius of sulphur is greater than that of phosphorus.

Because sulphur has half filled electronic configuration.

Because phosphorus has half filled electronic configuration.

Because ionisation energy decreases along the period in the 3^rd period.

Chlorine

Sulphur

Sodium

Bromine

Magnesium

Gallium

Germanium

Vanadium