Answer true or false.
(a) The ideal gas law assumes that there are no attractive forces between
molecules and therefore no liquids.
(b) Unlike a gas, whose molecules move freely in any direction, molecules in a
liquid are locked into fixed positions, giving the liquid a constant shape.
(c) Surface tension is the force that prevents a liquid from being stretched.
(d) Surface tension creates an elastic-like layer on the surface of a liquid.
(e) Water has a high surface tension because \(\mathrm{H}_{2} \mathrm{O}\) is a
small molecule.
(f) Vapor pressure is proportional to temperature-as the temperature of a
liquid sample increases, its vapor pressure also increases.
(g) When molecules evaporate from a liquid, the temperature of the liquid
drops.
(h) Evaporation is a cooling process because it leaves fewer molecules with
high kinetic energy in the liquid state.
(i) The boiling point of a liquid is the temperature at which its vapor
pressure equals the atmospheric pressure.
(j) \(\quad\) As the atmospheric pressure increases, the boiling point of a
liquid increases.
(k) The temperature of boiling water is related to how vigorously it is
boiling- -the more vigorous the boiling, the higher the temperature of the
water.
(l) The most important factor determining the relative boiling points of
liquids is molecular weight the greater the molecular weight, the higher the
boiling point.
\((\mathrm{m})\) Ethanol \(\left(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH},
\mathrm{bp} 78.5^{\circ} \mathrm{C}\right)\) has a greater
vapor pressure at \(25^{\circ} \mathrm{C}\) than water \(\left(\mathrm{H}_{2}
\mathrm{O}, \mathrm{bp} 100^{\circ} \mathrm{C}\right)\)
(n) Hexane \(\left(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2}
\mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}, \mathrm{bp} 69^{\circ}
\mathrm{C}\right)\)
has a higher boiling point than methane \(\left(\mathrm{CH}_{4}\right.\) bp
\(-164^{\circ} \mathrm{C}\) ) because hexane has more sites for hydrogen bonding
between its molecules than does methane.
(o) A water molecule can participate in hydrogen bonding through each of its
hydrogen atoms and through its oxygen atom.
(p) For nonpolar molecules of comparable molecular weight, the more compact
the shape of the molecule, the higher its boiling point.
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