Question

melting point of Ncl is more than Agcl3

Answer 1

We know that ionic compounds have more melting and boiling points than covalent compounds. 
compare NaCl , AlCl3 . 
NaCl is more ionic than AlCl3 because ionic character depends on size of cations as here anions are same more the size more the ionic character. 
Na+ has more size than Al+++. 
so the melting point of NaCl is much higher than that of AlCl3.