Halogens have electrons in their outer energy level. they tend to
gain an electron to fill the outer level forming an ion with a _ charge.

plz with #1& 2 but mostly one

Ifound this on google “these two compounds have a different ionic structure. caesium ion is larger in size when compared to the sodium ion. the charge gets more area to spread out evenly. so caesium chloride has a lower melting point than sodium chloride.” i hope this you for what your looking for

Yes you are correct use the scientific method