Boron has the least atomic size in 13^th group. After Boron, atomic radius is least for

Atomic radius….B<Ga<Al<In<Tl;

IP₁…..B>Tl>Ga>Al>In;

MP…B>Al>Tl>In>Ga;

Boron has gaint polymeric structure,Gallium exists as Ga₂ molecule(M.P = 302 K)

BP….B>Al>Ga>In>Tl:

Difference in B.P and M.P in Gallium is about 2300 K. It has wide liquid range.It is athermometric liquid.

Density…B<Al<Ga<In<Tl;

EN…B>Tl>In>Ga>Al;

${\mathrm{E}}_{{\mathrm{M}}^{3+}\mathrm{M}}^{\mathrm{o}}$is most -ve for Al and +ve for Tl;

${\mathrm{E}}_{{\mathrm{M}}^{+}/\mathrm{M}}^0$ is positive for Al;