Question 1

According to the Rutherford nuclear atom model, which statement is correct regarding the location of subatomic particles?

Accepted Answer

Protons and neutrons reside in the nucleus, while electrons are distributed throughout the atom.

Question 2

Which of the following is NOT an example of a chemical reaction?

Accepted Answer

Formation of water vapor

Question 3

Which one of the following is NOT an intensive property?

Accepted Answer

Mass

Question 4

What is the correct number of significant figures in the result of the following calculation? $$7.8 	imes 13.7 / 5.38$$

Accepted Answer

2

Question 5

An atom of $$^{127}_{54}Xe$$ has how many protons, neutrons, and electrons?

Accepted Answer

54 protons, 73 neutrons, 54 electrons

Question 6

Silver has two naturally occurring isotopes: $$^{107}Ag$$ and $$^{109}Ag. If $$the average atomic mass of silver is $$107.8682$$ amu, what is the fractional abundance of the lighter isotope?

Accepted Answer

$$0.4816$$

Question 7

Which pair of elements would you expect to exhibit the greatest similarity in their physical and chemical properties?

Accepted Answer

Cl and Br

Question 8

What is the name of the compound $$NaHCO_3$$?

Accepted Answer

Sodium bicarbonate

Question 9

Calculate the percentage by mass of hydrogen in $$P_2C_2N_2H_2.$$

Accepted Answer

$$2.04\%$$

Question 10

How many atoms/molecules are there in $$12 g of$$ $$NH_3$$?

Accepted Answer

$$4.24 	imes 10$$^{23}$$

Question 11

Propane ($$C_3H_8) $$reacts with oxygen to produce carbon dioxide and water. If $$22.0$$ grams of propane are combusted, how many grams of $$CO_2$$ are produced? (Molar mass of $$C_3H_8 = 44.1 g/$$mol, $$CO_2 = 44.0$ g/mol)

Accepted Answer

$$33.0 g$$

Question 12

A compound contains $$40.0\% C$$, $$6.7\% H$$, and $$53.3\% O by $$mass. The molecular weight is $$60 g/$$mol. What is the molecular formula?

Accepted Answer

$$C_2H_4O_2$$

Question 13

Lead(II) carbonate decomposes to give lead(II) oxide and carbon dioxide. If $$10.0 g of$$ $$PbCO_3 is $$heated, how many grams of $$CO_2$$ will be produced? ($$PbCO_3$$ molar mass = $$267 g/$$mol, $$CO_2$$ molar mass = $$44 g/$$mol)

Accepted Answer

$$1.65 g$$

Question 14

Which of the following solutions has the largest number of moles of chloride ions?

Accepted Answer

$$0.50 L of$$ $$0.50 M$$ $$CaCl_2$$

Question 15

A $$0.344 g $$sample of an ionic compound containing chloride ions and an unknown metal is dissolved in water and treated with excess $$AgNO_3. If$$ $$0.432 g of$$ $$AgCl$$ precipitate forms, what is the percent by mass of Cl in the original compound?

Accepted Answer

$$41.3\%$$

Question 16

Which of the following solutions is the best to use as a buffer for the reaction between acetic acid and sodium acetate?

Accepted Answer

$$\mathrm{pH} = \mathrm{p}K_a + \log \left( \frac{[\mathrm{A}^-]}{[\mathrm{HA}]} \right)$$

Question 17

In which reaction does the oxidation number of oxygen increase?

Accepted Answer

$$2H_2O_2 (aq) \rightarrow 2H_2O (l) + O_2$ (g)$$

Question 18

Calculate the concentration (in molarity) of an aqueous methanol produced when $$0.200 L of$$ $$0.40 M$$ $$CH_3OH is $$diluted to $$1.00 L.$$

Accepted Answer

$$0.08 M$$

Question 19

A $$34.62 mL $$volume of $$0.127 M$$ $$KOH$$ solution is needed to neutralize $$28.84 mL of$$ $$H_2SO_4$$ solution. What is the concentration of the $$H_2SO_4$$ solution in molarity? The net ionic equation is $$2KOH + H_2SO_4 \rightarrow 2H_2O + K_2SO_4.$$

Accepted Answer

$$0.076 M$$

General Chemistry: Foundational Concepts, Atomic Structure, Stoichiometry, and Chemical Reactions

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