$$0.45\% = \frac{\text{mass of NaCl}}{250\,\text{mL}} \times 100$$ $$\text{mass of NaCl} = \frac{0.45 \times 250}{100} = 1.125\,\text{g}$$

$$\text{pH} = -\log(1 \times 10$$^{-4}$$) = 4$$

$$\text{NH}_4^+ / \text{NH}_3$$

$$\text{HCl} + \text{NaOH} \rightarrow \text{NaCl} + \text{H}_2O$$

Question 1

Which of the following best describes a solution?

Accepted Answer

A homogeneous mixture of two or more substances where the solute is uniformly distributed within the solvent.

Question 2

A nurse needs to prepare 250 mL of a 0.45% (m/v) NaCl solution for a patient. How many grams of NaCl are required?

Accepted Answer

$$0.45\% = \frac{	ext{mass of NaCl}}{250\,	ext{mL}} 	imes 100$$ 
$$	ext{mass of NaCl} = \frac{0.45 	imes 250}{100} = 1.125\,	ext{g}$$

Question 3

Which of the following statements about colloids is TRUE?

Accepted Answer

Colloid particles are larger than solution particles but smaller than suspension particles.

Question 4

A red blood cell is placed in a hypertonic solution. What will happen to the cell?

Accepted Answer

Water will leave the cell, causing it to shrink (crenation).

Question 5

Which equation represents the dilution of a solution?

Accepted Answer

$$M_1$$ $$V_1$$ = $$M_2$$ $$V_2$$

Question 6

Which of the following is a strong electrolyte?

Accepted Answer

NaCl (sodium chloride)

Question 7

What is the pH of a solution with $$[H_3O^+] = 1 	imes 10$$^{-4}$$\,	ext{M}$$?

Accepted Answer

$$	ext{pH} = -\log(1 	imes 10$$^{-4}$$) = 4$$

Question 8

Which of the following best describes a buffer?

Accepted Answer

A solution that resists changes in pH when small amounts of acid or base are added.

Question 9

Which of the following pairs is a conjugate acid-base pair?

Accepted Answer

$$	ext{NH}_4^+ / 	ext{NH}_3$$

Question 10

Which of the following substances is most likely to dissolve in water?

Accepted Answer

CH$$_3F$$, because it is polar and can form hydrogen bonds with water.

Question 11

Which equation represents the neutralization reaction between HCl and NaOH?

Accepted Answer

$$	ext{HCl} + 	ext{NaOH} ightarrow 	ext{NaCl} + 	ext{H}_2O$$

Question 12

How many mL of 0.45% (m/v) NaCl solution can be made from 25.0 g of NaCl?

Accepted Answer

$$	ext{Volume} = \frac{25.0\,	ext{g}}{0.45\,	ext{g}/100\,	ext{mL}} = \frac{25.0 	imes 100}{0.45} = 5556\,	ext{mL}$$

Question 13

Which of the following is a weak acid?

Accepted Answer

Acetic acid ($$	ext{CH}_3	ext{COOH})$$

Question 14

Which of the following best describes the difference between saturated and unsaturated hydrocarbons?

Accepted Answer

Saturated hydrocarbons contain only single bonds, while unsaturated hydrocarbons contain double or triple bonds.

Question 15

Which of the following is the correct balanced equation for the combustion of propane ($$	ext{C}_3	ext{H}_8$$)?

Accepted Answer

$$	ext{C}_3	ext{H}_8 + 5	ext{O}_2 ightarrow 3	ext{CO}_2 + 4	ext{H}_2	ext{O}$$

Question 16

Which of the following best describes the difference between cis and trans isomers in alkenes?

Accepted Answer

Cis isomers have substituents on the same side of the double bond, while trans isomers have substituents on opposite sides.

Question 17

A 15.0 mL sample of 50 mM NaCl solution is diluted with 45.0 mL of water. What is the new concentration?

Accepted Answer

$$C_1$$ $$V_1$$ = $$C_2$$ $$V_2$$ 
$$C_2$$ = \frac{$$C_1$$ $$V_1$$}{$$V_2$$} = \frac{50 	imes 15.0}{60.0} = 12.5\,	ext{mM}$$

Question 18

Which of the following best describes the dissociation of NaCl in water?

Accepted Answer

$$	ext{NaCl} ightarrow 	ext{Na}^+ + 	ext{Cl}^-$$

Question 19

Which of the following is the correct formula for molarity?

Accepted Answer

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

Comprehensive Study Guide: Solutions, Acids & Bases, and Hydrocarbons

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