Fundamentals of General, Organic, and Biological Chemistry

John McMurry, David S. Ballantine, Carl A. Hoeger

Chapter 9

Solutions - all with Video Answers

Educators

Chapter Questions

Problem 1

Classify the following liquid mixtures as heterogeneous or homogeneous. Further classify each homogeneous mixture as a solution or colloid.
(a) Orange juice with pulp
(b) Apple juice
(c) Hand lotion
(d) Tea

Shahina -

Shahina -

Numerade Educator

Problem 2

Which of the following pairs of substances would you expect to form solutions?
(a) $\mathrm{CCl}_{4}$ and water
(b) Benzene $\left(\mathrm{C}_{6} \mathrm{H}_{6}\right)$ and $\mathrm{MgSO}_{4}$
(c) Hexane $\left(\mathrm{C}_{6} \mathrm{H}_{14}\right)$ and heptane $\left(\mathrm{C}_{7} \mathrm{H}_{16}\right)$
(d) Ethanol $\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right)$ and heptanol $\left(\mathrm{C}_{7} \mathrm{H}_{15} \mathrm{OH}\right)$

Shahina -

Numerade Educator

Problem 3

A solution is prepared by dissolving $12.5 \mathrm{~g}$ of $\mathrm{KBr}$ in $20 \mathrm{~mL}$ of water at $60^{\circ} \mathrm{C}$ (see Figure 9.3 ). Is this solution saturated, unsaturated, or supersaturated? What will happen if the solution is cooled to $10^{\circ} \mathrm{C}$ ?

John Nicolle

Numerade Educator

Problem 4

At $20^{\circ} \mathrm{C}(293 \mathrm{~K})$ and a partial pressure of $10^{5} \mathrm{~Pa}$, the solubility of $\mathrm{CO}_{2}$ in water is $0.169 \mathrm{~g} / 100 \mathrm{~mL}$. What is the solubility of $\mathrm{CO}_{2}$ at $33.3 \times 10^{5} \mathrm{~Pa}$ ?

John Nicolle

Numerade Educator

Problem 5

At $20^{\circ} \mathrm{C}(293 \mathrm{~K})$ and a partial pressure of $10^{5} \mathrm{~Pa}$, the solubility of $\mathrm{CO}_{2}$ in water is $0.169 \mathrm{~g} / 100 \mathrm{~mL}$. What is the solubility of $\mathrm{CO}_{2}$ at $33.3 \times 10^{5} \mathrm{~Pa}$ ?

John Nicolle

Numerade Educator

Problem 6

A metal alloy contains $15.8 \%$ nickel $(\mathrm{m} / \mathrm{m}) \%$. What mass of the metal alloy would contain $36.5 \mathrm{~g}$ of nickel?

John Nicolle

Numerade Educator

Problem 7

How would you use a $500.0 \mathrm{~mL}$ volumetric flask to prepare a $7.5 \%(\mathrm{v} / \mathrm{v})$ solution of acetic acid in water?

John Nicolle

Numerade Educator

Problem 8

In clinical lab reports, some concentrations are given in $\mathrm{mg} / \mathrm{dL}$. Convert a $\mathrm{Ca}^{2+}$ concentration of $8.6 \mathrm{mg} / \mathrm{dL}$ to mass / volume percent.

John Nicolle

Numerade Educator

Problem 9

What amounts of solute or solvent are needed to prepare the following solutions?
(a) Mass of glucose needed to prepare $125.0 \mathrm{~mL}$ of $16 \%(\mathrm{~m} / \mathrm{v})$ glucose $\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)$.
(b) Volume of water needed to prepare a $2.0 \%(\mathrm{~m} / \mathrm{v}) \mathrm{KCl}$ solution using $1.20 \mathrm{~g} \mathrm{KCl}$.

John Nicolle

Numerade Educator

Problem 10

What is the concentration in ppm of sodium fluoride in tap water that has been fluoridated by the addition of $32 \mathrm{mg}$ of NaF for every $20 \mathrm{~kg}$ of solution?

John Nicolle

Numerade Educator

Problem 11

The maximum amounts of lead and copper allowed in drinking water are $0.015 \mathrm{mg} / \mathrm{kg}$ for lead and $1.3 \mathrm{mg} / \mathrm{kg}$ for copper. Express these values in parts per million, and tell the maximum amount of each (in grams) allowed in $100 \mathrm{~g}$ of water.

John Nicolle

Numerade Educator

Problem 12

What is the molarity of a solution that contains $50.0 \mathrm{~g}$ of vitamin $\mathrm{B}_{1}$ hydrochloride (molar mass $=337 \mathrm{~g} / \mathrm{mol}$ ) in $160 \mathrm{~mL}$ of solution?

John Nicolle

Numerade Educator

Problem 13

How many moles of solute are present in the following solutions?
(a) $175 \mathrm{~mL}$ of $0.35 \mathrm{M} \mathrm{NaNO}_{3}$
(b) $480 \mathrm{~mL}$ of $1.4 \mathrm{M} \mathrm{HNO}_{3}$

John Nicolle

Numerade Educator

Problem 14

The concentration of cholesterol $\left(\mathrm{C}_{27} \mathrm{H}_{46} \mathrm{O}\right)$ in blood is approximately $5.0 \mathrm{mM}$. How many grams of cholesterol are in $250 \mathrm{~mL}$ of blood?

John Nicolle

Numerade Educator

Problem 15

Calcium carbonate reacts with $\mathrm{HCl}$ according to the following equation:
$$
2 \mathrm{HCl}(a q)+\mathrm{CaCO}_{3}(a q) \longrightarrow \mathrm{CaCl}_{2}(a q)+\mathrm{H}_{2} \mathrm{O}(l)+\mathrm{CO}_{2}(g)
$$
(a) How many moles of $\mathrm{HCl}$ are in $65 \mathrm{~mL}$ of $0.12 \mathrm{M} \mathrm{HCl}$ ?
(b) What mass of calcium carbonate (in grams) is needed for complete reaction with the $\mathrm{HCl}$ in (a)?

John Nicolle

Numerade Educator

Problem 16

Aqueous ammonia is commercially available at a concentration of $16.0 \mathrm{M}$. How much of the concentrated solution would you use to prepare $500.0 \mathrm{~mL}$ of a $1.25 M$ solution?

Nicole Krahulik

Nicole Krahulik

Numerade Educator

Problem 17

The Environmental Protection Agency has set the limit for arsenic in drinking water at 0.010 ppm. To what volume would you need to dilute $1.5 \mathrm{~L}$ of water containing 5.0 ppm arsenic to reach the acceptable limit?

John Nicolle

Numerade Educator

Problem 18

How many grams are in 1 Eq of the following ions? How many grams in $1 \mathrm{mEq}$ ?
(a) $\mathrm{K}^{+}$
(b) $\mathrm{Br}^{-}$
(c) $\mathrm{Mg}^{2+}$
(d) $\mathrm{SO}_{4}^{2-}$
(e) $\mathrm{Al}^{3+}$
(f) $\mathrm{PO}_{4}^{3-}$

Shahina -

Numerade Educator

Problem 19

How many grams are in 1 Eq of the following ions? How many grams in $1 \mathrm{mEq}$ ?
(a) $\mathrm{K}^{+}$
(b) $\mathrm{Br}^{-}$
(c) $\mathrm{Mg}^{2+}$
(d) $\mathrm{SO}_{4}^{2-}$
(e) $\mathrm{Al}^{3+}$
(f) $\mathrm{PO}_{4}^{3-}$

Shahina -

Numerade Educator

Problem 20

A solution is prepared by dissolving 0.67 mol of $\mathrm{MgCl}_{2}$ in $0.50 \mathrm{~kg}$ of water.
(a) How many moles of ions are present in solution?
(b) What is the change in the boiling point of the aqueous solution?

Rajesh Singh

Numerade Educator

Problem 21

When $1.0 \mathrm{~mol}$ of $\mathrm{HF}$ is dissolved in $1.0 \mathrm{~kg}$ of water, the boiling point of the resulting solution is $373.7 \mathrm{~K}\left(100.5^{\circ} \mathrm{C}\right) .$ Is HF a strong or weak electrolyte? Explain.

John Nicolle

Numerade Educator

Problem 22

The diagram to the right shows plots of vapor pressure versus temperature for a solvent and a solution.
(a) Which curve represents the pure solvent and which the solution?
(b) What is the approximate boiling-point elevation for the solution?
(c) What is the approximate concentration of the solution in $\mathrm{mol} / \mathrm{kg}$, if $1 \mathrm{~mol}$ of solute particles raises the boiling point of $1 \mathrm{~kg}$ of solvent by $3.63^{\circ} \mathrm{C}(3.63 \mathrm{~K}) ?$

Rajesh Singh

Numerade Educator

Problem 23

What is the freezing point of a solution of 1.0 mol of glucose in $1.0 \mathrm{~kg}$ of water?

John Nicolle

Numerade Educator

Problem 24

When $0.5 \mathrm{~mol}$ of a certain ionic substance is dissolved in $1.0 \mathrm{~kg}$ of water, the freezing point of the resulting solution is $-2.8^{\circ} \mathrm{C}(270.35 \mathrm{~K})$, How many ions does the substance give when it dissolves?

John Nicolle

Numerade Educator

Problem 25

What is the osmolarity of the following solutions?
(a) $0.35 M \mathrm{KBr}$
(b) $0.15 M$ glucose $+0.05 M \mathrm{~K}_{2} \mathrm{SO}_{4}$

John Nicolle

Numerade Educator

Problem 26

A typical oral rehydration solution (ORS) for infants contains $90 \mathrm{mEq} / \mathrm{L} \mathrm{Na}^{+}$, $20 \mathrm{mEq} / \mathrm{L} \mathrm{K}^{+}, 110 \mathrm{mEq} / \mathrm{L} \mathrm{Cl}^{-},$ and $2.0 \%(\mathrm{~m} / \mathrm{v})$ glucose (Molar mass $\left.=180 \mathrm{~g} / \mathrm{mol}\right)$
(a) Calculate the concentration of each ORS component in units of molarity.
(b) What is the osmolarity of the solution, and how does it compare with the osmolarity of blood plasma?

John Nicolle

Numerade Educator

Problem 27

Assume that two liquids are separated by a semipermeable membrane, with pure solvent on the right side and a solution of a solute on the left side. Make a drawing that shows the situation after equilibrium is reached.

Rajesh Singh

Numerade Educator

Problem 28

When $1 \mathrm{~mol}$ of $\mathrm{HCl}$ is added to $1 \mathrm{~kg}$ of water, the boiling point increases by $1.0^{\circ} \mathrm{C}(1.0 \mathrm{~K}),$ but when $1 \mathrm{~mol}$ of acetic acid, $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H},$ is added to $1 \mathrm{~kg}$ of water, the boiling point increases by only $0.5^{\circ} \mathrm{C}(0.5 \mathrm{~K})$. Explain.

Shahina -

Numerade Educator

Problem 29

HF is a weak electrolyte and HBr is a strong electrolyte. Which of the curves in the figure represents the change in the boiling point of an aqueous solution when 1 mole of HF is added to $1 \mathrm{~kg}$ of water, and which represents the change when $1 \mathrm{~mol}$ of $\mathrm{HBr}$ is added?

Rajesh Singh

Numerade Educator

Problem 30

Assume that you have two full beakers, one containing pure water (blue) and the other containing an equal volume of a $10 \%(\mathrm{w} / \mathrm{v})$ solution of glucose (green). Which of the drawings (a)-(c) best represents the two beakers after they have stood uncovered for several days and partial evaporation has occurred? Explain.

Rajesh Singh

Numerade Educator

Problem 31

A beaker containing $150.0 \mathrm{~mL}$ of $0.1 M$ glucose is represented by (a). Which of the drawings (b)-(d) represents the solution that results when $50.0 \mathrm{~mL}$ is withdrawn from (a) and then diluted hy a factor of $4 ?$

Rajesh Singh

Numerade Educator

Problem 32

What is the difference between a homogeneous mixture and a heterogeneous one?

Shahina -

Numerade Educator

Problem 33

How can you tell a solution from a colloid?

John Nicolle

Numerade Educator

Problem 34

What characteristic of water allows it to dissolve ionic solids?

Shahina -

Numerade Educator

Problem 35

Why does water not dissolve motor oil?

Shahina -

Numerade Educator

Problem 36

Which of the following are solutions?
(a) Italian salad dressing
(b) Rubbing alcohol
(c) Algae in pond water
(d) Mouthwash

Shahina -

Numerade Educator

Problem 37

Based on the predominant intermolecular forces, which of the following pairs of liquids are likely to be miscible?
(a) $\mathrm{H}_{2} \mathrm{SO}_{4}$ and $\mathrm{H}_{2} \mathrm{O}$
(b) $\mathrm{C}_{8} \mathrm{H}_{18}$ and $\mathrm{C}_{6} \mathrm{H}_{6}$
(c) $\mathrm{CH}_{2} \mathrm{Cl}_{2}$ and $\mathrm{H}_{2} \mathrm{O}$
(d) $\mathrm{CS}_{2}$ and $\mathrm{CCl}_{4}$

Shahina -

Numerade Educator

Problem 38

The solubility of $\mathrm{NH}_{3}$ gas in water at an $\mathrm{NH}_{3}$ pressure of $101,325 \mathrm{~Pa}$ and $25^{\circ} \mathrm{C}(298 \mathrm{~K})$ is $51.8 \mathrm{~g} / 100 \mathrm{~mL}$ and
$27.0 \mathrm{~g} / 100 \mathrm{~mL}$ at $50^{\circ} \mathrm{C}(323 \mathrm{~K})$
(a) What is the solubility of $\mathrm{NH}_{3}$ if its partial pressure is reduced to $30,000 \mathrm{~Pa} ?$
(b) How many moles of $\mathrm{NH}_{3}$ would be released from $1.0 \mathrm{~L}$ of a saturated $\mathrm{NH}_{3}$ solution if the temperature was increased from 25 to $50^{\circ} \mathrm{C}(298 \mathrm{~K}$ to $323 \mathrm{~K}$ )?

John Nicolle

Numerade Educator

Problem 39

The solubility of $\mathrm{CO}_{2}$ gas in water is $0.15 \mathrm{~g} / 100 \mathrm{~mL}$ at a $\mathrm{CO}_{2}$ pressure of $101,325 \mathrm{~Pa}$.
(a) What is the solubility of $\mathrm{CO}_{2}$ in a soft drink (which is mainly water) that was bottled under a $\mathrm{CO}_{2}$ pressure of $4.6 \times 10^{5} \mathrm{~Pa} ?$
(b) An atmospheric concentration of $380 \mathrm{ppm}, \mathrm{CO}_{2}$ corresponds to a partial pressure of $38.5 \mathrm{~Pa}$. What percentage of the $\mathrm{CO}_{2}$ originally dissolved in the solution in part (a) remains in solution after the soft drink reaches equilibrium with the ambient atmosphere?
(c) One bottle of soda is stored in a refrigerator at $3^{\circ} \mathrm{C}$ $(276 \mathrm{~K})$, and another is stored at room temperature $\left(25^{\circ} \mathrm{C}\right.$ or $\left.298 \mathrm{~K}\right)$. If both bottles are opened simultaneously, which one would exhibit greater carbonation (i.e., bubbles)? Explain.

Adriano Chikande

Adriano Chikande

Numerade Educator

Problem 40

Is a solution highly concentrated if it is saturated? Is a solution saturated if it is highly concentrated?

John Nicolle

Numerade Educator

Problem 41

How is mass/volume percent concentration defined and for what types of solutions is it typically used?

John Nicolle

Numerade Educator

Problem 42

How is molarity defined?

Shahina -

Numerade Educator

Problem 43

How is volume/volume percent concentration defined and for what types of solutions is it typically used?

John Nicolle

Numerade Educator

Problem 44

A $750.0 \mathrm{~mL}$ bottle of Listerine is of a $21 \%(\mathrm{v} / \mathrm{v})$ ethanol.
(a) What is the volume (in $\mathrm{mL}$ ) of ethanol in the bottle?
(b) If the density of ethanol is $0.789 \mathrm{~g} / \mathrm{mL}$ and the molar mass is $46.07 \mathrm{~g} / \mathrm{mol}$, calculate the molarity of ethanol in Listerine.

John Nicolle

Numerade Educator

Problem 45

A dilute aqueous solution of boric acid, $\mathrm{H}_{3} \mathrm{BO}_{3},$ is often used as an eyewash. How would you prepare $500.0 \mathrm{~mL}$ of a $0.50 \%(\mathrm{~m} / \mathrm{v})$ boric acid solution?

Vishal Sharma

Numerade Educator

Problem 46

Describe how you would prepare $250 \mathrm{~mL}$ of a $0.10 \mathrm{M}$ $\mathrm{NaCl}$ solution.

John Nicolle

Numerade Educator

Problem 47

Describe how you would prepare $1.50 \mathrm{~L}$ of a $7.50 \%(\mathrm{~m} / \mathrm{v})$ $\mathrm{Mg}\left(\mathrm{NO}_{3}\right)_{2}$ solution.

John Nicolle

Numerade Educator

Problem 48

What is the mass/volume percent concentration of the following solutions?
(a) $0.078 \mathrm{~mol} \mathrm{KCl}$ in $75 \mathrm{~mL}$ of solution
(b) 0.044 mol sucrose $\left(\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}\right)$ in $380 \mathrm{~mL}$ of solution

John Nicolle

Numerade Educator

Problem 49

The concentration of glucose in blood is approximately $90 \mathrm{mg} / 100 \mathrm{~mL}$. What is the mass/volume percent concentration of glucose? What is the molarity of glucose?

John Nicolle

Numerade Educator

Problem 50

How many moles of each substance are needed to prepare the following solutions?
(a) $50.0 \mathrm{~mL}$ of $8.0 \%(\mathrm{~m} / \mathrm{v}) \mathrm{KCl}$ (Molar mass = $74.55 \mathrm{~g} / \mathrm{mol})$
(b) $200.0 \mathrm{~mL}$ of $7.5 \%(\mathrm{~m} / \mathrm{v})$ acetic acid (Molar mass $=60.05 \mathrm{~g} / \mathrm{mol})$

John Nicolle

Numerade Educator

Problem 51

Which of the following solutions is more concentrated?
(a) $0.50 M \mathrm{KCl}$ or $5.0 \%(\mathrm{~m} / \mathrm{v}) \mathrm{KCl}$
(b) $2.5 \%(\mathrm{~m} / \mathrm{v}) \mathrm{NaHSO}_{4}$ or $0.025 \mathrm{M} \mathrm{NaHSO}_{4}$

John Nicolle

Numerade Educator

Problem 52

If you had only $23 \mathrm{~g}$ of $\mathrm{KOH}$ remaining in a bottle, how many milliliters of $10.0 \%(\mathrm{~m} / \mathrm{v})$ solution could you prepare? How many milliliters of $0.25 M$ solution?

John Nicolle

Numerade Educator

Problem 53

Over-the-counter hydrogen peroxide $\left(\mathrm{H}_{2} \mathrm{O}_{2}\right)$ solutions are $3 \%(\mathrm{~m} / \mathrm{v}) .$ What is this concentration in moles per liter?

John Nicolle

Numerade Educator

Problem 54

The lethal dosage of potassium cyanide $(\mathrm{KCN})$ in rats is $10 \mathrm{mg} \mathrm{KCN}$ per kilogram of body weight. What is this concentration in parts per million?

John Nicolle

Numerade Educator

Problem 55

What is the molarity of the following solutions?
(a) $12.5 \mathrm{~g} \mathrm{NaHCO}_{3}$ in $350.0 \mathrm{~mL}$ solution
(b) $45.0 \mathrm{~g} \mathrm{H}_{2} \mathrm{SO}_{4}$ in $300.0 \mathrm{~mL}$ solution
(c) $30.0 \mathrm{~g} \mathrm{NaCl}$ dissolved to make $500.0 \mathrm{~mL}$ solution

John Nicolle

Numerade Educator

Problem 56

How many grams of solute are in the following solutions?
(a) $200 \mathrm{~mL}$ of $0.30 \mathrm{M}$ acetic acid, $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}$
(b) $1.50 \mathrm{~L}$ of $0.25 \mathrm{M} \mathrm{NaOH}$
(c) $750 \mathrm{~mL}$ of $2.5 \mathrm{M}$ nitric acid, $\mathrm{HNO}_{3}$

John Nicolle

Numerade Educator

Problem 57

How many milliliters of a $0.75 M$ HCl solution do you need to obtain $0.0040 \mathrm{~mol}$ of $\mathrm{HCl} ?$

John Nicolle

Numerade Educator

Problem 58

Nalorphine, a relative of morphine, is used to combat withdrawal symptoms in heroin users. How many milliliters of a $0.40 \%(\mathrm{~m} / \mathrm{v})$ solution of nalorphine must be injected to obtain a dose of $1.5 \mathrm{mg}$ ?

John Nicolle

Numerade Educator

Problem 59

A flask containing $450 \mathrm{~mL}$ of $0.50 \mathrm{M} \mathrm{H}_{2} \mathrm{SO}_{4}$ was accidentally knocked to the floor. How many grams of $\mathrm{NaHCO}_{3}$ do you need to put on the spill to neutralize the acid according to the following equation?
$$
\begin{aligned}
\mathrm{H}_{2} \mathrm{SO}_{4}(a q)+2 \mathrm{NaHCO}_{3}(a q) & \longrightarrow \\
\mathrm{Na}_{2} \mathrm{SO}_{4}(a q)+2 \mathrm{H}_{2} \mathrm{O}(l)+2 \mathrm{CO}_{2}(g)
\end{aligned}
$$

John Nicolle

Numerade Educator

Problem 60

Sodium thiosulfate $\left(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\right),$ the major component in photographic fixer solution, reacts with silver bromide to dissolve it according to the following reaction:
$\mathrm{AgBr}(s)+2 \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}(a q) \longrightarrow$
$$
\mathrm{Na}_{3} \mathrm{Ag}\left(\mathrm{S}_{2} \mathrm{O}_{3}\right)_{2}(a q)+\mathrm{NaBr}(a q)
$$
(a) How many moles of $\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}$ would be required to react completely with $0.450 \mathrm{~g}$ of $\mathrm{AgBr}$ ?
(b) How many $\mathrm{mL}$ of $0.02 \mathrm{M} \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}$ contain this
number of moles?

Himanshu Kushwaha

Himanshu Kushwaha

Numerade Educator

Problem 61

What is the final volume of an orange juice prepared from $100.0 \mathrm{~mL}$ of orange juice concentrate if the final juice is to be $20.0 \%$ of the strength of the original?

John Nicolle

Numerade Educator

Problem 62

What is the final volume of $\mathrm{NaOH}$ solution prepared from $100.0 \mathrm{~mL}$ of $0.500 \mathrm{M} \mathrm{NaOH}$ if you wanted the final concentration to be $0.150 \mathrm{M}$ ?

John Nicolle

Numerade Educator

Problem 63

An aqueous solution that contains 285 ppm of potassium nitrate $\left(\mathrm{KNO}_{3}\right)$ is being used to feed plants in a garden. What volume of this solution is needed to prepare $2.0 \mathrm{~L}$ of a solution that is $75 \mathrm{ppm}$ in $\mathrm{KNO}_{3}$ ?

John Nicolle

Numerade Educator

Problem 64

What is the concentration of a $\mathrm{NaCl}$ solution, in $(\mathrm{m} / \mathrm{v}) \%,$ prepared by diluting $65 \mathrm{~mL}$ of a saturated solution, which has a concentration of $37(\mathrm{~m} / \mathrm{v}) \%$, to $480 \mathrm{~mL}$ ?

John Nicolle

Numerade Educator

Problem 65

Concentrated $(12.0 M)$ hydrochloric acid is sold for household and industrial purposes under the name "muriatic acid." How many milliliters of $0.500 \mathrm{M} \mathrm{HCl}$ solution can be made from $25.0 \mathrm{~mL}$ of $12.0 M \mathrm{HCl}$ solution?

John Nicolle

Numerade Educator

Problem 66

Dilute solutions of $\mathrm{NaHCO}_{3}$ are sometimes used in treating acid burns. How many milliliters of $0.100 \mathrm{M}$ $\mathrm{NaHCO}_{3}$ solution are needed to prepare $750.0 \mathrm{~mL}$ of $0.0500 \mathrm{M} \mathrm{NaHCO}_{3}$ solution?

John Nicolle

Numerade Educator

Problem 67

What is an electrolyte?

Manish Kumar

Numerade Educator

Problem 68

Give an example of a strong electrolyte and a nonelectrolyte.

Shahina -

Numerade Educator

Problem 69

What does it mean when we say that the concentration of $\mathrm{Ca}^{2+}$ in blood is $3.0 \mathrm{mEq} / \mathrm{L} ?$

John Nicolle

Numerade Educator

Problem 70

What is the total anion concentration (in $\mathrm{mEq} / \mathrm{L}$ ) of a solution that contains $5.0 \mathrm{mEq} / \mathrm{L} \mathrm{Na}^{+}, 12.0 \mathrm{mEq} / \mathrm{L} \mathrm{Ca}^{2+},$
and $2.0 \mathrm{mEq} / \mathrm{L} \mathrm{Li}^{+} ?$

John Nicolle

Numerade Educator

Problem 71

Kaochlor, a $10 \%(\mathrm{~m} / \mathrm{v}) \mathrm{KCl}$ solution, is an oral electrolyte supplement administered for potassium deficiency. How many milliequivalents of $\mathrm{K}^{+}$ are in a $30 \mathrm{~mL}$ dose?

John Nicolle

Numerade Educator

Problem 72

Calculate the mass needed for each of the following ion equivalents:
(a) $0.25 \mathrm{Eq} \mathrm{Ca}^{2+}$
(b) $75 \mathrm{mEq} \mathrm{K}^{+}$
(c) $199 \mathrm{mEg} \mathrm{SO}_{4}^{2-}$
(d) $0.65 \mathrm{Eq} \mathrm{PO}_{4}^{3-}$

John Nicolle

Numerade Educator

Problem 73

The concentration of $\mathrm{Cl}^{-}$ ion in blood is approximately $100 \mathrm{mEq} / \mathrm{L}$. How many milliliters of blood would be needed to obtain $1.0 \mathrm{~g}$ of $\mathrm{Cl}^{-}$ ions?

John Nicolle

Numerade Educator

Problem 74

Normal blood contains $3 \mathrm{mEq} / \mathrm{L}$ of $\mathrm{Mg}^{2+}$. How many milligrams of $\mathrm{Mg}^{2+}$ are present in $150.0 \mathrm{~mL}$ of blood?

John Nicolle

Numerade Educator

Problem 75

Which lowers the freezing point of $2.0 \mathrm{~kg}$ of water more, $0.20 \mathrm{~mol} \mathrm{NaOH}$ or $0.20 \mathrm{~mol} \mathrm{Ba}(\mathrm{OH})_{2} ?$ Both compounds are strong electrolytes. Explain.

John Nicolle

Numerade Educator

Problem 76

Which solution has the higher boiling point, $0.500 M$ glucose or $0.300 \mathrm{M} \mathrm{KCl}$ ? Explain.

John Nicolle

Numerade Educator

Problem 77

Methanol, $\mathrm{CH}_{3} \mathrm{OH}$, is sometimes used as an antifreeze for the water in automobile windshield washer fluids. How many moles of methanol must be added to $5.00 \mathrm{~kg}$ of water to lower its freezing point to $-10.0^{\circ} \mathrm{C}(263 \mathrm{~K}) ?$ (For each mole of solute, the freezing point of $1 \mathrm{~kg}$ of water is lowered $1.86^{\circ} \mathrm{C} / \mathrm{K} .$ )

John Nicolle

Numerade Educator

Problem 78

Hard candy is prepared by dissolving pure sugar and flavoring in water and heating the solution to boiling. What is the boiling point of a solution produced by adding $650 \mathrm{~g}$ of cane sugar (molar mass $342.3 \mathrm{~g} / \mathrm{mol}$ ) to $1.5 \mathrm{~kg}$ of water? (For each mole of nonvolatile solute, the boiling point of $1 \mathrm{~kg}$ of water is raised $0.51{ }^{\circ} \mathrm{C} / \mathrm{K} .$ )

John Nicolle

Numerade Educator

Problem 79

Why do red blood cells swell up and burst when placed in pure water?

John Nicolle

Numerade Educator

Problem 80

What does it mean when we say that a $0.15 \mathrm{M} \mathrm{NaCl}$ solution is isotonic with blood, whereas distilled water is hypotonic?

John Nicolle

Numerade Educator

Problem 81

Which of the following solutions has the higher osmolarity?
(a) $0.25 M \mathrm{KBr}$ or $0.20 \mathrm{M} \mathrm{Na}_{2} \mathrm{SO}_{4}$
(b) $0.30 \mathrm{M} \mathrm{NaOH}$ or $3.0 \%(\mathrm{~m} / \mathrm{v}) \mathrm{NaOH}$

John Nicolle

Numerade Educator

Problem 82

Which of the following solutions will give rise to a greater osmotic pressure at equilibrium: $5.00 \mathrm{~g}$ of $\mathrm{NaCl}$ in $350.0 \mathrm{~mL}$ water or $35.0 \mathrm{~g}$ of glucose in $400.0 \mathrm{~mL}$ water? For $\mathrm{NaCl}$, molecular mass $=58.5$ amu; for glucose, molecular mass $=180$ amu.

John Nicolle

Numerade Educator

Problem 83

A pickling solution for preserving food is prepared by dissolving $270 \mathrm{~g}$ of $\mathrm{NaCl}$ in $3.8 \mathrm{~L}$ of water. Calculate the osmolarity of the solution.

John Nicolle

Numerade Educator

Problem 84

An isotonic solution must be approximately 0.30 osmol $/ \mathrm{L}$. How much $\mathrm{KCl}$ is needed to prepare $175 \mathrm{~mL}$ of an isotonic solution?

John Nicolle

Numerade Educator

Problem 85

Uric acid, the principal constituent of some kidney stones, has the formula $\mathrm{C}_{5} \mathrm{H}_{4} \mathrm{~N}_{4} \mathrm{O}_{3}$. In aqueous solution, the solubility of uric acid is only $0.067 \mathrm{~g} / \mathrm{L}$. Express this concentration in $(\mathrm{m} / \mathrm{v}) \%$, in parts per million, and in molarity.

John Nicolle

Numerade Educator

Problem 86

Emergency treatment of cardiac arrest victims sometimes involves injection of a calcium chloride solution directly into the heart muscle. How many grams of $\mathrm{CaCl}_{2}$ are administered in an injection of $5.0 \mathrm{~mL}$ of a $5.0 \%(\mathrm{~m} / \mathrm{v})$ solution? How many milliequivalents of $\mathrm{Ca}^{2+}$ ?

John Nicolle

Numerade Educator

Problem 87

Nitric acid, $\mathrm{HNO}_{3},$ is available commercially at a concentration of $16 M$.
(a) What volume would you need to obtain $0.150 \mathrm{~mol}$ $\mathrm{HNO}_{3} ?$
(b) To what volume must you dilute this volume of $\mathrm{HNO}_{3}$ from part (a) to prepare a $0.20 \mathrm{M}$ solution?

John Nicolle

Numerade Educator

Problem 88

One test for vitamin $\mathrm{C}$ (ascorbic acid, $\mathrm{C}_{6} \mathrm{H}_{8} \mathrm{O}_{6}$ ) is based on the reaction of the vitamin with iodine:
$$
\mathrm{C}_{6} \mathrm{H}_{8} \mathrm{O}_{6}(a q)+\mathrm{I}_{2}(a q) \longrightarrow \mathrm{C}_{6} \mathrm{H}_{6} \mathrm{O}_{6}(a q)+2 \mathrm{HI}(a q)
$$
(a) A $25.0 \mathrm{~mL}$ sample of a fruit juice requires $13.0 \mathrm{~mL}$ of $0.0100 M \mathrm{I}_{2}$ solution for reaction. How many moles of ascorbic acid are in the sample?
(b) What is the molarity of ascorbic acid in the fruit juice?
(c) The Food and Drug Administration recommends that $60 \mathrm{mg}$ of ascorbic acid be consumed per day. How many milliliters of the fruit juice in part (a) must a person drink to obtain the recommended dosage?

Dr. Satish Ingale

Dr. Satish Ingale

Numerade Educator

Problem 89

A typical dosage of statin drugs for the treatment of high cholesterol is $10 \mathrm{mg}$. Assuming a total blood volume of 5.0 L, calculate the $(\mathrm{m} / \mathrm{v}) \%$ concentration of drug in the blood in units of $\mathrm{g} / 100 \mathrm{~mL}$.

John Nicolle

Numerade Educator

Problem 90

Assuming the density of blood in healthy individuals is approximately $1.05 \mathrm{~g} / \mathrm{mL},$ report the concentration of drug in Problem 9.89 in units of ppm.

John Nicolle

Numerade Educator

Problem 91

In European countries, a person with a blood alcohol concentration of $0.050 \%(\mathrm{v} / \mathrm{v})$ is considered legally drunk. What volume of total alcohol does this concentration represent, assuming a blood volume of $5.0 \mathrm{~L}$ ?

John Nicolle

Numerade Educator

Problem 92

Ammonia, $\mathrm{NH}_{3}$, is very soluble in water $(51.8 \mathrm{~g} / \mathrm{L}$ at $293 \mathrm{~K}$ and $101,325 \mathrm{~Pa})$
(a) Show how $\mathrm{NH}_{3}$ can hydrogen bond to water.
(b) What is the solubility of ammonia in water in moles per liter?

John Nicolle

Numerade Educator

Problem 93

Cobalt(II) chloride, a blue solid, can absorb water from the air to form cobalt(II) chloride hexahydrate, a pink solid. The equilibrium is so sensitive to moisture in the air that $\mathrm{CoCl}_{2}$ is used as a humidity indicator.
(a) Write a balanced equation for the equilibrium. Be sure to include water as a reactant to produce the hexahydrate.
(b) How many grams of water are released by the decomposition of $2.50 \mathrm{~g}$ of cobalt(II) chloride hexahydrate?

John Nicolle

Numerade Educator

Problem 94

How many milliliters of $0.150 \mathrm{M} \mathrm{BaCl}_{2}$ are needed to react completely with $35.0 \mathrm{~mL}$ of $0.200 \mathrm{M} \mathrm{Na}_{2} \mathrm{SO}_{4}$ ? How many grams of $\mathrm{BaSO}_{4}$ will be formed?

David Collins

Numerade Educator

Problem 95

Many compounds are only partially dissociated into ions in aqueous solution. Trichloroacetic acid $\left(\mathrm{CCl}_{3} \mathrm{CO}_{2} \mathrm{H}\right),$ for instance, is partially dissociated in water according to the equation
$$
\mathrm{CCl}_{3} \mathrm{CO}_{2} \mathrm{H}(a q) \longrightarrow \mathrm{H}^{+}(a q)+\mathrm{CCl}_{3} \mathrm{CO}_{2}^{-}(a q)
$$
For a solution prepared by dissolving $1.00 \mathrm{~mol}$ of trichloroacetic acid in $1.00 \mathrm{~kg}$ of water, $36.0 \%$ of the trichloroacetic acid dissociates to form $\mathrm{H}^{+}$ and $\mathrm{CCl}_{3} \mathrm{CO}_{2}^{-}$ ions.
(a) What is the total concentration of dissolved ions and molecules in $1 \mathrm{~kg}$ of water?
(b) What is the freezing point of this solution? (The freezing point of $1 \mathrm{~kg}$ of water is lowered $1.86^{\circ} \mathrm{C} / \mathrm{K}$ for each mole of solute particles.)

Emily Harris

Numerade Educator

Problem 96

Hyperbaric chambers, which provide high pressures (up to $6 \mathrm{~atm}$ ) of either air or pure oxygen, are used to treat a variety of conditions, ranging from decompression sickness in deep-sea divers to carbon monoxide poisoning. Look up the solubility of $\mathrm{O}_{2}, \mathrm{~N}_{2}, \mathrm{CO},$ and $\mathrm{CO}_{2}$ in water at standard temperature and pressure $(101,325 \mathrm{~Pa}, 298 \mathrm{~K})$.
(a) Explain the trends in relative solubility for these gases. (Refer to Section 8.2 and Section 9.2 )
(b) Explain how elevated pressures in a hyperbaric chamber be used to treat decompression sickness (excess $\mathrm{N}_{2}$ in blood) and carbon monoxide poisoning. (Refer to Section 7.9 and Section 9.5$)$

Rajesh Singh

Numerade Educator

Problem 97

Look up the maximum concentrations set by the U.S. Environmental Protection Agency for lead and cadmium in drinking water.
(a) What are these concentrations in milligrams per liter? In moles / L?
(b) Based on your answers to part (a), which is more toxic? Explain your answer.
(c) How many liters of water contaminated at this maximum level must you drink to consume $1.0 \mu \mathrm{g}$ of lead? To consume $1.0 \mu \mathrm{g}$ of cadmium?

Rajesh Singh

Numerade Educator

Problem 98

Look up the composition of Ringer's solution used in the treatment of burns and wounds.
(a) What is the molarity of each component?
(b) What is the osmolarity of the solution? Is it hypertonic, isotonic, or hypotonic with blood plasma $(0.30$ osmol $)$ ? Discuss possible medicinal reasons for the osmolarity of the solution.

Rajesh Singh

Numerade Educator

Problem 99

To prevent accumulation of ice on roads and sidewalks, many municipalities (and home-owners) will apply de-icing compounds to "melt" the ice by lowering the freezing point.
(a) Obtain a package of de-icing compound/mixture and identify the ingredients or look up the composition. Are the compounds ionic or molecular? Discuss possible reasons for the use of these compounds and for the specific compounds used in the formulations.
(b) Some de-icing compositions include dyes or colored compounds called indicators. Why?

Rajesh Singh

Numerade Educator

Problem 100

Many carbonate minerals are insoluble in water and appear in water pipes as "scale."
(a) What is "scale"? What are the solubilty equilibria involved in scale formation?
(b) Why is scale formation typically only a problem in hot water pipes?

Rajesh Singh

Numerade Educator

Problem 101

Research information related to dialysis and answer the following questions:
(a) What is the difference between hemodialysis and peritoneal dialysis?
(b) In hemodialysis, which substances diffuse out of the blood and into the dialysate (the solution used to remove waste products)? Which substances flow from the dialysate into the blood?
(c) Why is the level of hydrogen carbonate in the dialysate set at a slightly higher level than in normal blood?

Rajesh Singh

Numerade Educator