Periodicity

Question 1

classification of blocks

Answer 1

s, d , p

Question 2

first ionisation energy

Answer 2

energy required to remove 1 mole of electrons from one mole of a gaseous atoms to form 1 mole of gaseous 1+ ions

Question 3

trend in ionisation from g2 - 3

Answer 3

generally drops bc p orbital has higher energy level than s orbital and therefore less unclear attraction (slightly more shielding).

Question 4

trend in ionisation for group 5 - 6

Answer 4

decrease because group 6 has 2 electrons in orbital and repulsion makes it easier to remove electron.

Question 5

ionisation down a group

Answer 5

• nuclear charge increase overridden by shielding
• atomic radius increases
• shielding increases

Question 6

ionisation across period

Answer 6

• nuclear charge increases -> protons
• shielding remains roughly same
• atomic radius decreases

Question 7

metallic bonding structure

Answer 7

positive cations electrostatic ally attracted to negative ions (sea of delocalised electrons). form giant metallic structures

Question 8

metallic bonding properties

Answer 8

• high mp/ bp -> strong imp
• insoluble except when liquid
• good electrical conductor
• malleable - no bonds holding ions

Question 9

graphite bonding and structure, propeties

Answer 9

• diamond - 4 carbon bonds, covalently bonded (giant covalent lattice),
• tehtrahedyal (109.5)
• poor electrical conducter
• good thermal conductor
• high mp, bp
• soluble in any solvent

Question 10

graphene structure and properties

Answer 10

• 3 carbon covalent bonds - sheets bonded w week wdw forces -> slipper for lubricant, pencils
• good electrical conducture
• insoluble
• ## high mp

Question 11

graphite structure and propeties

Answer 11

• single sheet of graphene
• delocalised electron moves quickly around sheet as no layers -> best electrical conductor
• strong - de makes cv stronger

Question 12

allatropes of carbon

Answer 12

diamond, graphite, graphene, covalently bonded to form giant metallic lattice structures.

Question 13

change in mp across period 2, 3 in terms of structure and bonding

Answer 13

G1(giant) metallic, G2 (giant) metallic, G3 Giant covalent network, G4 giant covalent, G5, G6, G7 simple molecular, G0 monoatomic.

Question 14

why does be have higher mp than lithium

Answer 14

more delocalised electrons so more intermolecular forces and therefore stronger metallic bonds meaning requires more energy to break the bonds

Question 15

B has 4 covalent bonds just like carbon but which one has a higher boiling point

Answer 15

carbon - very strong covalent bonds compared to network of covalent bonds in B

Question 16

why does N,O,F have a higher bp than noble gases.

Answer 16

the week VDW forces between molecules are stronger than the very week London dispersion forces in noble gases.