Why the atomic radius of Gallium is less than that of aluminium?

Aniline is less basic than

Even though the cranium of elephant is larger than that of man , humans are considered more intelligent than elephant . Why is it so ?

Sodium is more metallic than Aluminium .

Is the density of CO_2 more or less than that of air?

The radius of the atom is of the order of

In Bohr's model, the atomic radius of the first orbit is gamma , then the atomic radius of the third orbit is______.

True/false: The speed of violet light is less than that of red light in prism.

Atomic size of carbon is less than that of boron. Explain the statement.

What does atomic radius and ionic radius really mean to you?

Answer the following questions: The atomic number of aluminium is 13, with the help of diagram , write the electronic configuration and valency.