module 3 periodicity

Question 1

periodicity

Answer 1

repeating trend in properties across each period

Question 2

ionisation energy state

Answer 2

gaseous

Question 3

first ionisation energy

Answer 3

energy needed required to remove one e- from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions

Question 4

first ionisation energy equation

Answer 4

Mg(g) -> Mg+(g) + e-

Question 5

value of each successive ionisation energy

Answer 5

increases
e- drawn slightly closer to nucleus

Question 6

successive ionisation energies provide evidence for

Answer 6

shells

Question 7

a large difference in ionisation number shows

Answer 7

change in energy level
new shell closer to nucleus
therefore harder to remove

Question 8

trends in first ionisation energy down group

Answer 8

atomic radius increases
shielding increases
attraction decreases

Question 9

trends in first ionisation energy across period

Answer 9

nuclear charge increases
atomic radius decreases ( contraction)
shielding constant

Question 10

falls across periods (ionisation energy) group 2 and 3

Answer 10

group 3: 3p subshell, higher energy
group 2: 3s
3p lost more easily than 3s

Question 11

falls across periods (ionisation energy) group 5 and 6

Answer 11

group 5: unpaired
group 6: e- lost from orbital containing paired e-
paired e- repel more, lost more easily

Question 12

metal structure

Answer 12

giant lattice

Question 13

metallic bonding

Answer 13

+ve metal ions
-ve delocalised e-
electrostatic forces

Question 14

why conduct?

Answer 14

moving charged particles (mcps)

Question 15

why do ionic compounds not conduct when solid?

Answer 15

ions fixed in lattice

Question 16

diamond structure

Answer 16

tetrahedral

Question 17

graphite structure

Answer 17

planar
weakly held together

Question 18

diamond and silicon

Answer 18

do not conduct

Question 19

graphite and graphene

Answer 19

conduct

Question 20

melting points

Answer 20

*increase for metals in same period
as you go across more highly charged ions and more delocalised e-
*giant covalent structures (B,C,Si) highest mp due to strong covalent bonds
*for simple molecules mp depends on London forces so no of e-