1 Which of the following substances can form hydrogen bonds?
Substances: (1) CH3 COCH3 ; (2) CH3 OH; (3) C2 H6 ; (4) HCOOH
A) compounds 1 and 2 B) compounds 1 and 3 C) compounds 1, 2, and 3 D) compounds 2 and 4 E) compounds 1, 2, and 4 2 Samples of which one of the following substances exhibits both dipole-dipole forces and hydrogen bonding?A) HCl B) PH3 C) Br2 D) H2 E) CH3 NH2 3 In which of the following substances are dispersion forces likely to be the most important intermolecular interaction in determining the melting and boiling points?A) Br2 B) H2 S C) CO D) HCl E) ICl 4 At a given temperature, which of the following liquids should have the highest viscosity?A) CH2 Br2 B) HOCH2 CH2 OH C) CH2 CH2 OH D) CH3 Cl E) CH3 OCH3 5 Krypton crystallizes in a structure that has four Kr atoms in each unit cell, and the unit cell is a cube. The edge length of the unit cell is 0.559 nm. Calculate the density of crystalline Kr, in kg/m3 .A) 9.97 x 10-13 kg/m3 B) 3.14 x 103 kg/m3 C) 3.14 kg/m3 D) 3.19 x 103 kg/m3 6 At room temperature, SiO2 is a solid, whereas CO2 is a gas. This is becauseA) both are molecular, but the dispersion forces between SiO2 molecules are stronger because SiO2 is the larger of the two compounds. B) both are molecular, but CO2 is linear whereas SiO2 is bent, and therefore has dipole-dipole attractions. C) CO2 is molecular, whereas SiO2 is a covalent network solid. D) CO2 is molecular whereas SiO2 is ionic. 7 Which of the following compounds should have the highest melting point?A) MgCl2 B) BCl3 C) NCl3 D) CCl4 8 Which of the following substances would have the greatest electrical conductivity in the solid state?A) K B) KI C) I D) IF 9 Use the Clausius-Clapeyron equation to estimate the boiling point of water at 24.0 torr pressure. The average (Hvap for water over the relevant temperature range is 42.34 kJ/mol).A) 33.2 o C B) 25 o C C) 298 o C D) 80 o C 10 Acetic acid has a heat of fusion of 10.8 kJ/mol and a heat of vaporization of 24.3 kJ/mol. The estimated value for the heat of sublimation of acetic acid isA) -13.5 kJ/mol. B) -35.1 kJ/mol. C) 13.5 kJ/mol. D) 17.6 kJ/mol. E) 35.1 kJ/mol.