Electronegativity & Polarity

Question 1

Electronegativity Difference (ΔEN)

Answer 1

• Electronegativity difference between two elements determines if its ionic or covalent bond
• If there is H2O, do not multiple H by 2, just add both elements

Question 2

Non-Polar Covalent Bonds

Answer 2

• Equal pull on electrons
• EN=0 or nearly identical
• 0 < ΔEN ≤ 0.4

Question 3

Polar Covalent Bonds

Answer 3

• One atom is pulling atoms closer to them
• Not a equal pull
• The higher the electronegativity number, the greater pull they have
• 0.4 < ΔEN < 1.7

Question 4

Ionic Bonds

Answer 4

• Complete transfer of electrons giving complete charge
• ΔEN ≥ 1.7

Question 5

Drawing Conventions for Polar Covalent bonds

Answer 5

Partial charge (δ+ and δ-)
- It is partially charged since we are not transferring electrons, we are sharing them
Bond dipoles/dipole moments
- Arrows that point to the most electronegative atom
Not all molecules containing polar covalent bonds are polar molecules

Question 6

Polar Molecules

Answer 6

• One end is slightly positive and other is slightly negative
• One atom is pulling electrons slightly more

Question 7

Non-Polar Molecules

Answer 7

• All Molecular elements are non-polar
• They are sharing electrons with its own element (EN=0)
• No arrows

Question 8

Bent shape

Answer 8

• 2 bonding pair and lone pairs in central atom
• Polar bond if it has covalent bonds
• Water
• AX 2 E2

Question 9

Trigonal Pyramidal Shape

Answer 9

• 3 bonding pairs
• 1 lone pair
• Polar bond if it has covalent bonds
• Ammonia
• Ax3E

Question 10

Linear Shape

Answer 10

• 2 bonding pairs
• No lone pairs
• Not polar bond if it has covalent bonds
• Carbon dioxide
• AX2

Question 11

Trigonal Planar

Answer 11

• 3 bonding pairs
• No lone pairs
• Not polar bond if it has covalent bonds
• AX3

Question 12

Tetrahedral Shape

Answer 12

• 4 bonding pairs
• No lone pairs
• nonpolar bond if it has covalent bond
• AX4