Chapter 12

What is hydrogen bonding? How can you tell whether a compound has hydrogen bonding?

What are ion-dipole forces? What kinds of substances contain ion-dipole forces?

What is a molecular solid? What kinds of forces hold molecular solids together?

What is an ionic solid? What kinds of forces hold ionic solids together?

Which evaporates more quickly: \(55 \mathrm{~mL}\) of water in a beaker with a diameter of \(4.5 \mathrm{~cm}\) or \(55 \mathrm{~mL}\) of water in a dish with a diameter of \(12 \mathrm{~cm}\) ? Why?

One milliliter of water is poured onto one hand, and one milliliter of acetone (fingernail-polish remover) is poured onto the other. As they evaporate, they both feel cool. Which one feels cooler and why? (Hint: Which substance is more volatile?)

Spilling water over your skin on a hot day will cool you down. Spilling vegetable oil over your skin on a hot day will not. Explain the difference.

Several ice cubes are placed in a beaker on a lab bench, and their temperature, initially at \(-5.0^{\circ} \mathrm{C}\), is monitored. Explain what happens to the temperature as a function of time. Make a sketch of how the temperature might change with time. (Assume that the lab is at \(25^{\circ} \mathrm{C}\).)

Water is put into a beaker and heated with a Bunsen burner. The temperature of the water, initially at \(25^{\circ} \mathrm{C}\), is monitored. Explain what happens to the temperature as a function of time. Make a sketch of how the temperature might change with time. (Assume that the Bunsen burner is hot enough to heat the water to its boiling point.)

Which causes a more severe burn: spilling \(0.50 \mathrm{~g}\) of \(100{ }^{\circ} \mathrm{C}\) water on your hand or allowing \(0.50 \mathrm{~g}\) of \(100^{\circ} \mathrm{C}\) steam to condense on your hand? Why?