Organic Chemistry Boiling Point Quiz

Boiling point is the temperature at which the vapor pressure of the liquid is equal to the atmospheric pressure and change its state from a liquid to a gas. In terms of intermolecular interactions the b.p. represents the energy required to overcome the various intermolecular attractions binding the molecules as a liquid (e.g. dipole-dipole attraction and hydrogen bonding). Therefore, the ______ of a liquid is also an indicator of the strength of the attractive forces between the liquid’s molecules.

Factors affecting boiling point (b.p) 1. Pressure 2. Molecular weight 3. Impurities 4. Structure of the molecule & intermolecular interactions: A. Branching B. Polarity C. Van der Waal interactions D. H-bonding

a) When the ______ is less than 1 atm , the boiling point of the liquid is less than its normal b.p. b) When P = 1 atm, the b.p. of the liquid is called normal boiling point. c) When P is greater than 1 atm, the b.p. of the liquid is greater than its normal b.p.

A solution has a higher boiling point than a pure solvent. The b.p. of pure H2O is 100 oC, but that b.p. can be elevated by adding a solute such as a salt.

By increasing Molecular weight b.p increase.