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Consider dissolving these two molecules in water: Even though the solute-separation step for ethanol requires more energy than does the solute-separation step for diethyl ether, ethanol is more soluble in water. Explain why.

Henry's law tells us that the solubility \(s\) of a gas in a liquid increases as the pressure \(P\) of the gas increases. Which of the following mathematical expressions of Henry's law is correct? Explain your choice and explain why the other two expressions are incorrect. (Hint: The \(k\) is just a constant of proportionality and can be ignored.) (a) \(s=k P\) (b) \(s=k / P\) (c) \(s=k P / P\)

Why do most solids become more soluble in water with increasing temperature? (Hint: Think about what happens to the water molecules as temperature increases.)

When a small amount of soap is added to a beaker of water, the soap molecules end up positioning themselves at the surface (hence soaps are often called surfactants): Explain why the soap molecules migrate to the surface, and why they orient themselves with their hydrocarbon tails sticking out of the water.

Soap molecules not only form spherical micelles in water, they also form spherical vesicles, which you can picture as thick-walled hollow spheres. Here is a cross section of such a vesicle, with the blue regions representing water: Unlike a micelle, a vesicle traps water in its interior. What gives a vesicle this ability? (If you are having trouble with the difference between micelles and vesicles, think of a baseball and a hollow rubber ball. The baseball, with no empty space inside, is analogous to the micelle, and the hollow ball is analogous to the vesicle.)

A student combines \(60.0 \mathrm{~mL}\) of \(0.250 \mathrm{M} \mathrm{NaOH}\) with \(60.0 \mathrm{~mL}\) of \(0.125 \mathrm{M} \mathrm{Ba}(\mathrm{OH})_{2}\). What is the hydroxide ion molar concentration in the resulting solution?

How many grams of \(\mathrm{NaOH}\) are needed to prepare \(500.0 \mathrm{~mL}\) of \(0.300 \mathrm{M} \mathrm{NaOH}\) solution?

How many moles of potassium permanganate, \(\mathrm{KMnO}_{4}\), are there in \(28.68 \mathrm{~mL}\) of a \(5.20 \times 10^{-3} \mathrm{M}\) solution of \(\mathrm{KMnO}_{4} ?\)

What is the volume in milliliters of \(0.0150 \mathrm{M}\) \(\mathrm{NaOH}\) solution required to neutralize \(50.0 \mathrm{~mL}\) of \(0.0100 \mathrm{MHNO}_{3}(a q) ?\)

A solution is prepared by dissolving \(5.00 \mathrm{~g}\) of sucrose, \(\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}\), in \(1.00 \mathrm{~L}\) of water. What is the percent by mass concentration of sucrose? (The density of water is \(1.00 \mathrm{~g} / \mathrm{mL}\) ).