Exam 3: Water and Life

Identical heat lamps are arranged to shine on two identical containers, one containing water and one methanol (wood alcohol), so that each liquid absorbs the same amount of energy minute by minute. The covalent bonds of methanol molecules are nonpolar, so there are no hydrogen bonds among methanol molecules. Which of the following graphs correctly describes what will happen to the temperature of the water and the methanol?

Which of the following graphs describes the relationship between [H₃O⁺] and pH?

The partial negative charge in a molecule of water occurs because ________.

Measurements show that the pH of a particular lake is 4.0. What is the hydroxide ion concentration of the lake?

Thermal energy of the water in a bathtub is ________ than in a freshly brewed coffee pot because of its ________.

Which of the following can be attributed to water's high specific heat?

A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg.)

A dietary Calorie equals 1 kilocalorie. One kilocalorie equals ________.

The molar mass of glucose is 180 grams per mole (g/mol). Which of the following procedures should you carry out to make a 1 M solution of glucose? In 0.8 liter (L) of water, dissolve ________.

When an ionic compound such as sodium chloride (NaCl) is placed in water, the component atoms of the NaCl crystal dissociate into individual sodium ions (Na⁺) and chloride ions (Cl⁻). In contrast, the atoms of covalently bonded molecules (e.g., glucose, sucrose, glycerol) do not generally dissociate when placed in aqueous solution. Which of the following solutions would be expected to contain the greatest number of solute particles (molecules or ions)?

Water has many exceptional and useful properties. Which is the rarest property among compounds?

One mole (mol) of glucose (molecular mass = 180 daltons) is ________.

How does 0.5 M sucrose (molecular mass 342) solution compare to 0.5 M glucose (molecular mass 180) solution?

The cities of Portland, Oregon, and Minneapolis, Minnesota, are at about the same latitude, but Minneapolis has much hotter summers and much colder winters than Portland. Why?

What is the pH of a solution with a hydroxyl ion (OH⁻) concentration of 10⁻¹⁰ M?