Electronegatvity & Polarity

Question 1

What is electronegativity?

Answer 1

The power of an atom to attract the bonding pair of electrons in a covalent bond.

Question 2

How does electronegativity change throughout the periodic table?

Answer 2

• increases across periods
• increases up the group

Question 3

What is the difference in electronegativity in a covalent bond?

Answer 3

0

Question 4

What is the difference in electronegativity in a polar covalent bond?

Answer 4

0 to 1.8

Question 5

What is the difference in electronegativity in an ionic bond?

Answer 5

Greater than 1.8

Question 6

What is a non-polar bond?

Answer 6

Bonded electron pair is shared equally between the bonded atoms
—> atoms are the same
—> atoms have the same or similar electronegativity

Question 7

What is a polar bond?

Answer 7

Bonded electron pair is shared unequally between the bonded atoms.
—> atoms are different
—> atoms have different electronegativity values

Question 8

What type of dipole is present in a polar covalent bond?

Answer 8

Permanent dipole as it does not change

Question 9

Which shaped molecules have an overall dipole?

Answer 9

Non-symmetrical (pyramidal, non-linear)

Question 10

Which shaped molecules have no overall dipole?

Answer 10

Symmetrical (linear, trigonal planar, tetrahedral, octahedral)

Question 11

How do polar solvents dissolve giant ionic lattice’s?

Answer 11

• water molecules surround the ions
• +ve ions are attracted to slightly -ve molecules
• -ve ions are attracted to slightly +ve molecules
• so the ionic lattice breaks down as it dissolves