Polarity and IMF Flashcards
The distribution of electrical charge around atoms, chemical groups, or molecules
Polarity
Ways to Determine Polarity of Molecules
- Electronegativity Difference
- Molecular Shape
Group of Atoms bonded together
Molecules
Ability of an atom to attract electrons towards itself in a chemical bond?
Electronegativity
Types of Covalent Bonds
Polar and Non-Polar
If Electronegativity is below 0.4, what is the bond?
Nonpolar Covalent
Types of Bonds
Covalent and Ionic
If Electronegativity is 0.4 to 1.69, what is the bond?
Polar Covalent
If Electronegativity is above 1.69, what is the bond?
Ionic
Electronegativity Difference Formula
EN = I Ea - Eb I
Bonds that share electrons
Covalent
Bonds that bonded despite having different electronegativities
Ionic
Which Covalent bond is more stable?
Non-Polar
Kinds of Molecular Shapes
Linear
Trigonal Planar
Bent or Angular
Tetrahedral
Trigonal Pyramidal
Trigonal Bipyramidal
Octahedral
Which Molecular Shapes are considered POLAR?
Bent or Angular and Trigonal Pyramidal
Bonds with Equal Pairs
Nonpolar
Bonds with Unequal Pairs
Polar
What do we call an Electron with no pair?
Lone Pair
Which Molecular Shapes are considered NONPOLAR?
Linear
Trigonal Planar
Tetrahedral
Trigonal Bipyramidal
Octahedral
What Shape is this?
S = C = S
Linear
What Shape is this?
H II H = C = H II H
Tetrahedral
Forces within a molecule or ionic compound (inner)
Intramolecular Forces
Forces between two molecules or ions and molecules (outer)
Intermolecular Forces
Name the three (3) states
Solid, Liquid, Gas
The MORE CLOSELY bonded the molecules
The HIGHER the IMF
Bounds molecules together
IMF
Strong IMF
Solid
Moderate IMF
Liquid
Low IMF
Gas
What do you use to break a bond?
Temperature
What are the types of Ion?
Cation (Na+) and Anion (Na-)
A molecule with net electric charge
Ion (Na)
Where one side of the atom is negatively charged (-) - typically the HEAD of a molecule, and another is positively charged (+) - typically the TAIL of a molecule
Dipole
Types of IMF
London Dispersion (Dispersion Forces)
Dipole-Dipole Forces
Hydrogen Bond
Ion-Dipole Bond
Default intermolecular force that is present in POLAR and NON-POLAR molecules. Caused by fluctuations in the electron distribution. Electrons are UNEVENLY DISTRIBUTED.
London Dispersion (Dispersion Forces)
Can only exist in POLAR molecules, where positive end is attracted to negative neighbor.
Dipole-Dipole Forces
Special type of Dipole-Dipole (only for POLAR atoms). Can only occur when an H (hydrogen) atom is connected with either of the following: N (nitrogen), O (oxygen), or F (flourine)
Hydrogen Bond
Attractive forces between an ion (Na) and POLAR molecule.
Ion-Dipole Forces
IMF of Boiling Point
Stronger IMF = Higher Boiling Point
IMF of Melting (endothermic) or Freezing (exothermic) Point
Stronger IMF = Higher Melting and Freezing Point
What is the Strongest type of IMF?
Ion-Dipole Forces
What is the Weakest type of IMF
London Dispersion (Dispersion Forces)
Which has stronger IMF between BONDS?
Polar Bonds
IMF of Surface Tension
Stronger IMF = Greater Surface Tension
IMF of Viscosity
Stronger IMF = More Viscous
Temperature at which boiling occurs
Boiling Point
Temperature at which solid and liquid phases coexist in equilibrium
Melting and Freezing Point
Measure of Elastic Force in the surface of a liquid
Surface Tension
Measure of fluid’s resistance to flow
Viscosity
