Chem Mod 1

A liquid boils when..

Which of the following statements concerning intermolecular forces is/are CORRECT?1. Dipole-dipole attractions occur in all molecules that contain polar bonds, regardless of whether the molecule has a dipole.2. Induced dipole/induced dipole forces exist in all molecular solids.3. Hydrogen bonding only occurs in all molecules containing OH bonds.

Which one of the following molecules will exhibit dipole-dipole intermolecular forces as a pure liquid?

Hydrogen bonding is present in all of the following molecular solids EXCEPT

Below are the vapor pressures of some compounds measured at 20oC. Which of these would you expect to have the highest boiling point?

Each of the following substances is a liquid at -50oC. Place these liquids in order of increasing vapor pressure.dimethyl ether (CH3OCH3), propane (C3H8), ethanol (CH3CH2OH)

Which property of water allows a razor blade to float on it without sinking?

Which two of the following materials are most likely to be amorphous solids: water, nylon, glass, potassium nitrate?

Which of the following changes will be exothermic?

At its boiling point of 58.8 oC, 3.66 kJ of heat is required to vaporize 19.5 g of bromine (Br2). What is the molar enthalpy of vaporization of bromine?

The process of condensation happens when which of the following occurs?

Which of the following statements is/are CORRECT?1. If the intermolecular forces in a liquid decrease, the normal boiling point of the liquid decreases.2. If the temperature of a liquid increases, the equilibrium vapor pressure increases.3. If the surface area of a liquid increases, the equilibrium vapor pressure of the liquid increases.

Given the following liquids and their boiling points, which has the highest vapor pressure at its normal boiling point?

Which of the following is NOT true with regard to water?

Which of the following phase transitions is/are endothermic?1. liquid water freezing to a solid at its normal freezing point of 0.0 °C.2. the sublimation of solid carbon dioxide into the gas phase.3. gaseous sulfur dioxide condensing into a liquid at its boiling point of –10.0 °C.

Which of the following statements concerning intermolecular forces is/are CORRECT? 1. Dipole-dipole attractions occur in all molecules that contain polar bonds, regardless of whether the molecule has a dipole. 2. Induced dipole/induced dipole forces exist in all molecular solids. 3. Hydrogen bonding only occurs in all molecules containing OH bonds.

For which of the following species are the dispersion forces strongest?

The boiling points of some group 7A hydrides are tabulated below.gas b.p. (°C)NH3 –33PH3 –88AsH3 –62Which intermolecular force or bond is responsible for the high boiling point of NH3 relative to PH3 and AsH3?

You are given the following boiling point data. Which of the liquids would you expect to have the highest vapor pressure at room temperature?

Which of the following properties of water can be attributed to hydrogen bonding?1. high melting point2. high heat of vaporization3. low vapor pressure4. high surface ten

Which of the following crystallizes in a metallic lattice?

Ammonia, NH3, is used as a refrigerant. At its boiling point of –33 oC, the standard enthalpy of vaporization of ammonia is 23.3 kJ/mol. How much heat is released when 50.0 g of ammonia is condensed at –33 oC?

Given the following compounds and their vapor pressures (VP). Arrange them in increasing (lowest to highest) order of boiling points.ethane (C2H6); VP= 841 mm Hgpentane (C5H12); VP=420 mm Hgisopropyl alcohol (C3H5OH); VP=31.5 mm Hgacetone (C3H6O); VP=185 mm Hg

Which of the following molecules has the highest vapor pressure?

endothermic

exothermic