trend in the properties of elements in period 3

Question 1

what happens with groups 1,2,23 (what do they form?)

Answer 1

they form giant metallic structures , they loose their outer electrons. ionic bonds

Question 2

what does silicon do?

Answer 2

group 4 -forms 4 covalent bonds . (macromolecular /giant covalent structure)

Question 3

what do elements in groups 5,6,7 do ?

Answer 3

they are non metals , they wither accept electrons to form ionic bonds or share electrons to form covalent bonds .they form

Question 4

what does argon do?

Answer 4

group o=unreactive

Question 5

which element have high melting points and why?

Answer 5

those on the left(sodium is the exception). they tend to have giant structures

Question 6

which elements have low melting points and why?

Answer 6

those on the right.molecular or atomic structure

Question 7

describe and explain melting points in period 3 ?

Answer 7

the melting and boiling points increase from sodium to aluminium because of the strength of metallic bonding .
as you go from left to right the charge on the ion increases so more electrons join the delocalised electron sea that holds the giant metallic lattice together .
the melting and boiling points of non metals with molecular structures depend on the size of the van der waals forces between the molecules so it depend on the electron number and how closely they can pack together. This means the melting point of non metals are ordered (highest to lowest ) : S,P,Cl