Periodic table

Question 1

Aufbau principle

Answer 1

subshells are filled in order from lowest energy to highest energy and that lower subshell energy levels will be filled before higher energy subshells

Question 2

Pauli exclusion principle

Answer 2

a max of 2 electrons in orbital with opposite spin

Question 3

Core charge

Answer 3

num of protons -num of electrons in the inner shell

measure of net attractive force felt by the valence shell electrons towards the nucleus

Question 4

Atomic radius down a group

Answer 4

Increases

• the number of occupied energy levels increases
• core charge remains constant

Question 5

Atomic radius across a period

Answer 5

decreases
number of occupied energy levels remains constant
core charge increases=valence shell electrons pulled in more

Question 6

Electronegativity

Answer 6

the strength with which atoms of an element attract electrons when they are chemically combined with another element

Question 7

Electronegativity down a group

Answer 7

decreases

• num of occupied energy levels increases
• nuclear charge increases, however electron shielding also increases so core charge stays the same.

Question 8

Electronegativity across a period

Answer 8

increases

• atomic radius decreases
• core charge increases

Question 9

First Ionisation energy

Answer 9

the energy required to remove an electron from each of a mole of gaseous atoms

Question 10

Ionisation energy down a group

Answer 10

decreases

• atomic radius increases
• core charge remains constant
• therefore less energy required to remove an electron

Question 11

Ionisation across a period

Answer 11

increases

• atomic radius decreases
• core charge increases
• therefore more energy is required to remove an electron

Question 12

Reactivity of metals across a period

Answer 12

decreases

• core charge increases
• general increases in energy required to remove an electron

Question 13

reactivity of metals down a group

Answer 13

increases
core charge remains the same
-energy levels+ electron shielding increases
- decrease in energy required to remove an electron

Question 14

Reactivity of non metals down a group

Answer 14

decrease

Question 15

reactivity of no metals across a period

Answer 15

increases