$$\frac{5.0}{100} \times 100\% = 5.0\%$$

$$-\log(2.0 \times 10$$^{-7}$$) = 6.7$$

A solution with [OH$$^-$$] = $$1 \times 10$$^{-2}$$ M

Question 1

Which of the following statements best explains why water has a higher boiling point than methane (CH$$_4) $$under standard conditions?

Accepted Answer

Water molecules form strong hydrogen bonds, which require more energy to break.

Question 2

Arrange the following atoms in order of increasing electronegativity: Ba, Ca, Ga, Se.

Accepted Answer

Ba \u003c Ca \u003c Ga \u003c Se

Question 3

Which molecule is polar?

Accepted Answer

H$$_2O$$

Question 4

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

Accepted Answer

Hydrogen bonding

Question 5

Which of the following compounds is most likely to be soluble in water?

Accepted Answer

Ethanol (C$$_2H$_5OH)$$

Question 6

A solution is prepared by dissolving 5.0 g of NaCl in 95 g of water. What is the percent concentration of NaCl in the solution?

Accepted Answer

$$\frac{5.0}{100} 	imes 100\% = 5.0\%$$

Question 7

Which of the following ionic compounds is insoluble in water?

Accepted Answer

AgCl

Question 8

What is the molarity of a solution containing 39.3 g of Ca(NO$$_3$$)$$_2 in 735 mL of $$solution? (Molar mass of Ca(NO$$_3$$)$$_2 = 164 g/$$mol)

Accepted Answer

$$\frac{39.3}{164} = 0.240$$ mol; $$\frac{0.240}{0.735} = 0.327$$ mol/L

Question 9

Which of the following is a strong electrolyte when dissolved in water?

Accepted Answer

NaCl

Question 10

Which of the following statements about acids and bases is correct?

Accepted Answer

A strong base dissociates completely in water.

Question 11

What is the balanced chemical equation for the neutralization of H$$_2SO$_4$$ with NaOH?

Accepted Answer

$$\mathrm{H_2SO_4(aq) + 2NaOH(aq) \rightarrow Na_2SO_4(aq) + 2H_2O(l)}$$

Question 12

If you have 3.0 L of 0.60 M H$$_2SO$_4$$ solution, how many moles of NaOH are needed to neutralize it?

Accepted Answer

3.6 moles (since $$\mathrm{H_2SO_4}$$ requires 2 moles of NaOH per mole)

Question 13

A solution has a hydrogen ion concentration of $$2.0 	imes 10$$^{-7}$$ M. What is its pH?

Accepted Answer

$$-\log(2.0 	imes 10$$^{-7}$$) = 6.7$$

Question 14

Which of the following solutions is the most basic?

Accepted Answer

A solution with [OH$$^-$$] = $$1 	imes 10$$^{-2}$$ M

Question 15

Which of the following best describes the role of carbonate and bicarbonate ions in maintaining blood pH?

Accepted Answer

They act as buffers to resist changes in blood pH.

Question 16

Which of the following is a correct statement about the density of ice compared to liquid water?

Accepted Answer

Ice is less dense than liquid water because its molecules are farther apart due to hydrogen bonding.

Question 17

Which of the following compounds will NOT conduct electricity when dissolved in water?

Accepted Answer

Sucrose (C$$_{12}H$_{22}O$_{11})$$

Question 18

A solution has a pH of 3.6. What is the hydrogen ion concentration?

Accepted Answer

$$[H^+] = 10$$^{-3.6}$$ = 2.5 	imes 10$$^{-4}$$ M

General Chemistry – CHM110: Water, Electronegativity, Polarity, and Hydrogen Bonding

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