EL6

Question 1

Na

Answer 1

giant metallic lattice
strong metallic bond

Question 2

Mg

Answer 2

giant metallic lattice
strong metallic bond

Question 3

Al

Answer 3

giant metallic lattice
strong metallic bond

Question 4

Si

Answer 4

Giant covalent network
strong covalent bonds

Question 5

P4

Answer 5

simple covalent
weak IM forces

Question 6

S8

Answer 6

simple covalent
weak IM forces

Question 7

Cl2

Answer 7

simple covalent
weak IM forces

Question 8

Ar

Answer 8

monatomic
weak IM forces

Question 9

why does the group 4 element have the highest melting point in a period?

Answer 9

giant covalent structure takes a lot of energy to break the strong covalent bonds between atoms

Question 10

Why do melting points increase from group 1-3?

Answer 10

they have metallic structures - attraction between the positive ions and delocalised electrons increases, so more energy is required to break the bonds

Question 11

what is the trend in atomic radius:

Answer 11

a. down a group
increases (number of shells increases)
b. across a period
decreases (nuclear charge increases but number of shells/shielding stays the same)

Question 12

Explain why atomic emission spectra are unique to each element

Answer 12

the gaps between energy levels are unique to each element, therefore the frequecies emitted are unique to each element

Question 13

why do the spaces between lines get closer together at higher frequencies?

Answer 13

the gaps between energy levels decrease the further the energy levels are from the nucleus

Question 14

Which atoms can have more than 8 electrons in their outer shells when bonded (expanded octets) and why?

Answer 14

p-block elements from Phosphorus onwards. they can use empty d orbitals for bonding

Question 15

arrange themselves as far apart as possible to minimise repulsion

Answer 15

• lone pairs repel more than bonding pairs