Explain the Atomic radius

Explanation:

everything can be found in the picture above. Hope this helps

Ithink is a because if say increased in electronegativity

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).