Q: Calculate the formula mass of sodium sulfate, Na$$_2SO$_4.$$

$$2 \times 23 + 32 + 4 \times 16 = 142 g/$$mol

Q: What is the pH of a solution with a hydrogen ion concentration of $$[H^+] = 1 \times 10$$^{-4}$$ M?

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

Q: Which of the following statements about the mole is correct?

One mole of any substance contains $$6.022 \times 10$$^{23}$$ particles.

Q: A solution is made by diluting 50.0 mL of 6.0 M HCl to a final volume of 300.0 mL. What is the final concentration?

$$C_1V_1 = C_2V_2$$, $$C_2$$ = \frac{6.0 \times 50.0}{300.0} = 1.0$$ M

Question 1

Which law states that a chemical compound always contains exactly the same proportion of elements by mass?

Accepted Answer

Law of Definite Proportions

Question 2

A sample of glucose (C$$_6H$_{12}O$_6) $$has a mass of 180 g. How many moles of glucose are present? (Molar mass of glucose = 180 g/mol)

Accepted Answer

$$\frac{180}{180} = 1$$ mole

Question 3

Which of the following best describes an ionic bond?

Accepted Answer

A bond formed by the transfer of electrons from a metal to a nonmetal

Question 4

What is the empirical formula for a compound containing 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass?

Accepted Answer

CH$$_2O$$

Question 5

Which of the following is the correct name for HCl (aq)?

Accepted Answer

Hydrochloric acid

Question 6

Calculate the formula mass of sodium sulfate, Na$$_2SO$_4.$$

Accepted Answer

$$2 	imes 23 + 32 + 4 	imes 16 = 142 g/$$mol

Question 7

A solution is prepared by dissolving 5.85 g of NaCl in enough water to make 0.500 L of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.5 g/mol)

Accepted Answer

$$\frac{5.85}{58.5} = 0.1$$ mol$$,\ \frac{0.1}{0.5} = 0.2 M$$

Question 8

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

Accepted Answer

NaNO$$_3$$

Question 9

Which factor will NOT increase the solubility of a solid solute in water?

Accepted Answer

Decreasing the amount of solvent

Question 10

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

Accepted Answer

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

Question 11

A spectrophotometer is used to measure the absorbance of a solution. According to Beer's Law, which equation relates absorbance (A) to concentration (c)?

Accepted Answer

$$A = \epsilon c l$$

Question 12

Which of the following best describes the difference between an empirical formula and a molecular formula?

Accepted Answer

The empirical formula shows the simplest whole-number ratio of atoms, while the molecular formula shows the actual number of atoms in a molecule.

Question 13

A compound contains 27.3% carbon and 72.7% oxygen by mass. What is the empirical formula?

Accepted Answer

CO

Question 14

Which of the following statements about the mole is correct?

Accepted Answer

One mole of any substance contains $$6.022 	imes 10$$^{23}$$ particles.

Question 15

Which of the following is a correct representation of the chemical formula for aluminum sulfate?

Accepted Answer

Al$$_2(SO$_4$$)$$_3$$

Question 16

A solution is made by diluting 50.0 mL of 6.0 M HCl to a final volume of 300.0 mL. What is the final concentration?

Accepted Answer

$$C_1V_1 = C_2V_2$$, $$C_2$$ = \frac{6.0 	imes 50.0}{300.0} = 1.0$$ M

Question 17

Which of the following best explains why NaCl dissolves in water?

Accepted Answer

The positive and negative ions in NaCl are attracted to the partial charges on water molecules.

Question 18

Which of the following is NOT a molecular compound?

Accepted Answer

NaCl

Question 19

A student determines that a compound contains 2.00 mol of hydrogen, 1.00 mol of sulfur, and 4.00 mol of oxygen. What is the empirical formula?

Accepted Answer

H$$_2SO$_4$$

Question 20

Which of the following statements about solution equilibrium is correct?

Accepted Answer

At equilibrium, the rate of dissolution equals the rate of precipitation.

General Chemistry Study Guide: Atomic Theory, Chemical Bonds, Solutions, and Equilibrium

Guida di studio - Domande di pratica

Study guide - Flashcard