An ionic solid does not conduct electricity in the solid state because the ions are held together by attractive forces and cannot move from their positions in the crystal structure. Of the solid melts or dissolves in water, the ions are free to move and carry a(n) current.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8