Movement along the periodic table

Question 1

Atomic Radius

Answer 1

The total distance between the centre of the nucleus and outermost valence electron

Question 2

Ionisation energy

Answer 2

The amount of energy required to remove a valance electron from an atom/ion from 1 mole of gaseous state

Question 3

Electronegativity

Answer 3

Measure of an atom’s ability to attract a bonding pair of electrons

Question 4

Core Charge/ Effective nuclear charge

Answer 4

Attractive forces felt by the valence electrons toward the positive nucleus
(- to +)

Question 5

Shielding effect

Answer 5

Repulsion force felt by outer electrons, from inner electrons.

Question 6

Octet rule

Answer 6

Achieve a full valance shell (Stable)

Question 7

What happens down a group

Answer 7

As we go down a group the number of electron shells increase.

Question 8

What happens across a period

Answer 8

As we go across a period the number of protons increase however the number of electron shells stay the same.

Question 9

Atomic radius down a group

Answer 9

As we go down a group, the number of electron valence shells increase. This results in a greater distance between the positively charged nucleus and outer valence electrons, therefore the atomic radius increase.

Question 10

Atomic radius across a period

Answer 10

As we go across a period, the number of protons increase however the number of valence shells stay the same. Hence, the electrostatic force of attraction between the positive nucleus and negative outer most valence electrons increases, resulting the atomic radius to decrease

Question 11

ionisation energy down a group

Answer 11

The number of electron valance shells increases as we go down a group. This results in an increase atomic radius and outer most valence electrons feeling a greater shielding effect (repulsion) from inner electrons. This decreases the electrostatic force of attraction between the positive nucleus and negative outer most valence electrons. Resulting to a decrease in ionisation energy.

Question 12

ionisation energy across a period

Answer 12

The number of protons increases as we go across a period, however the number of valance shells stay the same. This increases the electrostatic force of attraction between the positive nucleus and negative outer most valence electrons. The core charge is meant to increase. Resulting to a greater amount of energy required to remove a valance electron. Hence ionisation energy increases

Question 13

electronegativity down a group

Answer 13

Down a group, the number of electron valence shells increase. This results to a decrease in the electrostatic force of attraction between the positive charged nucleus and negative bonding pair of electrons from a neighbouring atom. Hence, it is harder to attract a bonding pair of electrons. Resulting the electronegativity to decrease.

Question 14

Electronegativity across a period

Answer 14

Across a period, the number of protons increases, however the number of electron valance shells stay the same. This increases the electrostatic force of attraction between the positive nucleus and negative bonding pair of electrons from a neighbouring atom. Hence, it is easier to attract a bonding pair of electron. Resulting the electronegativity to increase.