Bond polarity

Question 1

Electronegativity

Answer 1

Power of an atom to attract the electron density in a covalent bond towards itself

Question 2

Pauling Scale

Answer 2

Measure of electronegativity

Question 3

Depends on:

Answer 3

• nuclear charge
• distance between the nucleus and outer shell electrons
• shielding of the nuclear charge by electrons in the inner shells
• Smaller the atom, the greater its electronegativity
• larger the nuclear charge, greater the electronegativity

Question 4

Trends in electronegativity

Answer 4

• up a group it increases as less shielding by electrons in inner shells
• across a period it increases as the nuclear charge increases and atom becomes smaller

Question 5

Polarity

Answer 5

The electron distribution in a covalent bond between elements with different electronegativities will be unsymmetrical. This produces a polar covalent bond, and may cause a molecule to have a permanent dipole.