Intermolecular forces (Electronegativity) Flashcards
Define “electronegativity”
The ability of an atom to attract a pair of electrons in a covalent bond.
How does electronegativity change across the periodic table?
- Down the groups, electronegativity DECREASES
- Across the periods, electronegativity INCREASES
State the most electronegative elements.
NOF
- Nitrogen (3.0)
- Oxygen (3.5)
- Fluorine (4.0)
What types of bonding depend on the electronegativity of a molecule?
Pure covalent, polar covalent and ionic
List the electronegativity differences for the types of bonds
- Pure covalent (x < 0.4)
- Polar covalent (0.4 < x < 1.8)
- Ionic (x > 1.8)
POLAR COVALENT - (1.8 < x < 2.1)
Define “pure covalent”
The bond between atoms with similar or same electronegativity and has no ionic character.
Vice versa for ionic bonds etc…
Displayed here are the electronegativity values for Copper and Bromine. Calculate electronegativity difference and state the type of bond.
Cu - 1.9
Br - 3.0
- 0 - 1.9 = 1.1
- 1 is in between 0.4 and 1.8. Therefore, it has a polar covalent bond.
Assume molecules have only 1 atom of each element.