3.1.1.3 Electron configuration- Trends

Question 1

property of the electrons the ‘up’ and ‘down’ arrows representing electrons represent

Answer 1

Spin

Question 2

why electrons which occupy the 2p sub-levels have a higher energy than electrons in the 2s sub-level

Answer 2

Further from nucleus

or more shielded

Question 3

why atomic radius decreases across Period 3 from sodium to chlorine

Answer 3

Number of protons increases

Electrons in same shell

Question 4

the element in Period 3 that has the highest melting point and explanation

Answer 4

Silicon / Si
covalent (bonds)
Strong or many of the (covalent) bonds need to be broken / needs a lot of energy to break the (covalent) bonds

Question 5

the element in Period 3 that has the highest electronegativity value

Answer 5

Chlorine / Cl

Question 6

whether an atom of 88Sr will have an atomic radius that is larger than, smaller than or the same as the atomic radius of 87Rb

Answer 6

Smaller
Bigger nuclear charge / more protons in Sr
Similar/same shielding

Question 7

the trend in atomic radius of the Period 3 elements from sodium to chlorine

Answer 7

Decreases
Increasing nuclear charge/ increasing number of protons
Electrons in same shell or level/ same shielding/ similar shielding

Question 8

Definition: electronegativity

Answer 8

Ability (or power) of an atom to attract electron density (or electrons or ve charge)
in a covalent bond

Question 9

the trend in electronegativity values across Period 3 from sodium to chlorine

Answer 9

Trend: increases
Explanation: nuclear charge (number of protons) increases
electrons in same shell