1. Which of the following has the highest boiling point? a. NH3 PH3 AsH3 b. CH4 SiH4 GeH4 c. Ne Ar d. HF HCl HBr e. SO2 KCl N2 Kr SnH4 Xe HI 6. Which of species can exhibit hydrogen bonding among themselves? a. H2Te H2Se H2O H2S b. C6H6 NH3 B2H6 CaH2 c. C3H8 H2 LiH HF 9. At which temperature does water have its greatest density? 0 oC 4 oC 96 oC 100 oC 10. Classify in the order of increasing boiling points the following compounds : CH3CH2OH, CH3COCH3 and CH3OH 11.Which of the following compounds would you expect to be the most volatile A. C2H8 B. H2S C. CH3OH D. CH4 12. Which of the following compounds would you expect to have the highest boiling point? Why? a. CH3CH2OCH3 b. CH3CH2CH2OH c. CH3CH2CH3 Solution: CH3CH2CH2OH is the only one of the three molecules that contains OH groups which will result in strong cohesive forces due to intermolecular hydrogen bonding. 13. All the following are liquids at room temperature. Which would you expect to be the most volatile? a. CH3CH2OH (propanol) b. Acetone c. Ethanol Solution: Acetone does not contain an OH group and so there is no hydrogen bonding. Acetone would be the most volatile. 14. Which of the following liquids would you expect to be least volatile? a. pentane b. hexane c. octane d. decane