$$\frac{10}{100} \times 100 = 10\%$$

$$M = \frac{\text{moles of solute}}{\text{liters of solution}}$$

Question 1

Which of the following statements best explains why oil and water do not mix?

Accepted Answer

Oil molecules are nonpolar and water molecules are polar, so their intermolecular forces are not compatible.

Question 2

A sealed container of water is heated until the vapor pressure equals atmospheric pressure. What is occurring at this point?

Accepted Answer

The water is boiling.

Question 3

Which intermolecular force is primarily responsible for the high boiling point of water?

Accepted Answer

Hydrogen bonding

Question 4

A solution is prepared by dissolving 10 g of NaCl in 90 g of water. What is the mass/mass percent concentration of NaCl in the solution?

Accepted Answer

$$\frac{10}{100} 	imes 100 = 10\%$$

Question 5

Which of the following best describes a colloid?

Accepted Answer

A homogeneous mixture with particles between 1 and 1000 nanometers that remain suspended.

Question 6

Which of the following is a strong electrolyte?

Accepted Answer

NaCl (sodium chloride) dissolved in water

Question 7

A patient receives an intravenous (IV) solution that is hypotonic compared to their blood plasma. What is the most likely effect?

Accepted Answer

Water will flow into the patient's cells, possibly causing them to swell and burst.

Question 8

Which of the following best describes the relationship between temperature and the solubility of gases in water?

Accepted Answer

As temperature increases, the solubility of gases in water decreases.

Question 9

Which of the following is the correct formula for calculating molarity?

Accepted Answer

$$M = \frac{	ext{moles of solute}}{	ext{liters of solution}}$$

Question 10

Which statement about acids and bases is true according to the Brønsted-Lowry definition?

Accepted Answer

An acid donates a proton (H$$^+$$), and a base accepts a proton.

Question 11

What is the pH of a solution with $$[H^+] = 1 	imes 10$$^{-4}$$ M?

Accepted Answer

$$pH = 4$$

Question 12

Which of the following is a buffer system in the human body?

Accepted Answer

A mixture of H$$_2CO$_3$$ and HCO$$_3^- in $$blood

Question 13

Which of the following best describes Le Chatelier’s Principle?

Accepted Answer

If a system at equilibrium is disturbed, the system will shift to counteract the disturbance and restore equilibrium.

Question 14

Which of the following is true about amphipathic compounds?

Accepted Answer

They contain both polar and nonpolar regions, allowing them to act as emulsifiers.

Question 15

A solution contains 0.2 mol of Ca$$^{2+}$$ ions. How many equivalents of charge does this represent?

Accepted Answer

$$0.2 	ext{ mol} 	imes 2 	ext{ Eq/mol} = 0.4 	ext{ Eq}$$

Question 16

Which of the following is a correct statement about the ionization of water at 25°C?

Accepted Answer

$$[H^+][OH^-] = 1 	imes 10$$^{-14}$$

Question 17

Which of the following is the correct equilibrium constant expression for the reaction $$aA + bB \rightleftharpoons cC + dD$$?

Accepted Answer

$$K = \frac{[C]^c[D]^d}{[A]^a[B]^b}$$

Question 18

Which of the following is a property of bases?

Accepted Answer

They turn litmus paper blue.

Question 19

A solution is prepared by mixing 50 mL of ethanol with 150 mL of water. What is the volume/volume percent concentration of ethanol?

Accepted Answer

$$\frac{50}{200} 	imes 100 = 25\%$$

States of Matter, Solution Chemistry, and Acids/Bases: CHEM 1150 Ch. 7, 8, & 9.1-9.5 Study Notes

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