1.5.2 Bond Polarity (Physical Chemistry)

Question 1

Electronegativity is

Answer 1

the power of an atom to attract the pair of electrons in a covalent bond towards itself

Question 2

The electron distribution in a covalent bond between elements with different electronegativities will be

Answer 2

unsymmetrical

Question 3

This phenomenon arises from

Answer 3

the positive nucleus’s ability to attract the negatively charged electrons, in the outer shells, towards itself

Question 4

The Pauling scale is used to

Answer 4

assign a value of electronegativity for each atom

Question 5

First three rows of the periodic table showing electronegativity values diagram

Answer 5

Question 6

Fluorine is the

Answer 6

most electronegative atom on the Periodic Table, with a value of 4.0 on the Pauling Scale

Question 7

Fluorine is best at

Answer 7

attracting electron density towards itself when covalently bonded to another atom

Question 8

Electron distribution in the C-F bond of fluoromethane diagram

Answer 8

Question 9

Attraction exists between

Answer 9

the positively charged protons in the nucleus and negatively charged electrons found in the energy levels of an atom

Question 10

An increase in the number of protons leads to

Answer 10

an increase in nuclear attraction for the electrons in the outer shells

Question 11

An increased nuclear charge results in

Answer 11

an increased electronegativity

Question 12

The atomic radius is

Answer 12

the distance between the nucleus and electrons in the outermost shell

Question 13

Electrons closer to the nucleus are

Answer 13

more strongly attracted towards its positive nucleus

Question 14

Those electrons further away from the nucleus are

Answer 14

less strongly attracted towards the nucleus

Question 15

Tn increased atomic radius results in

Answer 15

electronegativity decreases

Question 16

Filled energy levels can

Answer 16

shield (mask) the effect of the nuclear charge causing the outer electrons to be less attracted to the nucleus

Question 17

The addition of extra shells and subshells in an atom will

Answer 17

cause the outer electrons to experience less of the attractive force of the nucleus

Question 18

Sodium (period 3, group 1) has higher electronegativity than caesium (period 6, group 1) as

Answer 18

it has fewer shells and therefore the outer electrons experience less shielding than in caesium

Question 19

An increased number of inner shells and subshells will result in

Answer 19

a decreased electronegativity

Question 20

Electronegativity varies across

Answer 20

periods and down the groups of the periodic table

Question 21

Down a group
- There is a decrease in

Answer 21

electronegativity

Question 22

Down a group
- The nuclear charge

Answer 22

increases as more protons are being added to the nucleus

Question 23

Down a group
- Each element has an extra filled electron shell, which

Answer 23

increases shielding

Question 24

Down a group
- The addition of the extra shells

Answer 24

increases the distance between the nucleus and the outer electrons resulting in larger atomic radii

Question 25

Down a group
- Overall, there is

Answer 25

decrease in attraction between the nucleus and outer bonding electrons

Question 26

Electronegativity decreases going down the groups of the periodic table diagram

Answer 26

Question 27

Across a period
- Electronegativity

Answer 27

increases

Question 28

Across a period
- The nuclear charge

Answer 28

increases with the addition of protons to the nucleus

Question 29

Across a period
- Shielding remains

Answer 29

relatively constant across the period as no new shells are being added to the atoms

Question 30

Across a period
- The nucleus has

Answer 30

an increasingly strong attraction for the bonding pair of electrons of atoms across the period of the periodic table

Question 31

Across a period
- The nucleus has an increasingly strong attraction for the bonding pair of electrons of atoms across the period of the periodic table, this results in

Answer 31

smaller atomic radii

Question 32

Electronegativity increases going across the periods of the Periodic Table diagram

Answer 32