Question 1

Which of the following best describes the difference between mass and weight?

Accepted Answer

Mass is the amount of matter in an object, while weight is the force exerted by gravity on that mass.

Question 2

A student measures the temperature of a solution as 25.0 °C. What is this temperature in Kelvin?

Accepted Answer

$$25.0 + 273.15 = 298.15\ \mathrm{K}$$

Question 3

Which of the following is the correct prefix and symbol for $$10^{-3}$$?

Accepted Answer

Milli-, m

Question 4

Which subatomic particle determines the atomic number of an element?

Accepted Answer

Proton

Question 5

An isotope of carbon has 6 protons and 8 neutrons. What is its mass number?

Accepted Answer

$$6 + 8 = 14$$

Question 6

Which of the following is the correct formula for the ionic compound formed between magnesium and chlorine?

Accepted Answer

$$\mathrm{$$MgCl_2$$}$$

Question 7

What is the charge on the iron ion in the compound $$\mathrm{Fe_2O_3}$$?

Accepted Answer

$$+3$$

Question 8

Balance the following chemical equation: $$\mathrm{C_2H_6} + \mathrm{O_2$} \rightarrow \mathrm{CO_2$} + \mathrm{H_2O}$$

Accepted Answer

$$2\ \mathrm{C_2H_6} + 7\ \mathrm{O_2$} \rightarrow 4\ \mathrm{CO_2$} + 6\ \mathrm{H_2O}$$

Question 9

A reaction mixture contains 5.0 g of $$\mathrm{H_2$}$$ and 20.0 g of $$\mathrm{O_2$}. $$Which is the limiting reactant in the formation of water?

Accepted Answer

$$\mathrm{H_2$}$$

Question 10

Which of the following compounds is most soluble in water?

Accepted Answer

$$\mathrm{NaCl}$$

Question 11

Which of the following is a strong electrolyte?

Accepted Answer

$$\mathrm{HCl}$$

Question 12

A solution is prepared by diluting 50.0 mL of 6.0 M $$\mathrm{$$HNO_3$$} to a $$final volume of 300.0 mL. What is the final concentration?

Accepted Answer

$$C_1V_1 = C_2V_2$$; $$C_2$$ = \frac{C_1V_1}{$$V_2$$} = \frac{6.0 	imes 50.0}{300.0} = 1.0\ \mathrm{M}$$

Question 13

Which statement best explains why ionic compounds conduct electricity when dissolved in water?

Accepted Answer

Ions are free to move in solution, allowing electrical current to pass.

Question 14

Which of the following is the correct electron configuration for a neutral sodium atom ($$Z=11$$)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^1$$

Question 15

Which of the following best describes the trend in atomic radius across a period in the periodic table?

Accepted Answer

Atomic radius decreases from left to right.

Question 16

A sample of gas occupies 2.0 L at 1.0 atm. If the pressure is increased to 4.0 atm at constant temperature, what is the new volume?

Accepted Answer

$$P_1V_1 = P_2V_2$$; $$V_2$$ = \frac{P_1V_1}{$$P_2$$} = \frac{1.0 	imes 2.0}{4.0} = 0.5\ \mathrm{L}$$

Question 17

Which of the following is NOT a property of metals?

Accepted Answer

High solubility in water

Question 18

Which of the following best describes a limiting reactant in a chemical reaction?

Accepted Answer

The reactant that is completely consumed first, limiting the amount of product formed.

Question 19

Which of the following ions is most likely to form a precipitate with $$\mathrm{SO_4$^{2-}} in $$aqueous solution?

Accepted Answer

$$\mathrm{Ba$$^{2+}$$}$$

General Chemistry Fundamentals: Matter, Energy, Atomic Structure, and Chemical Reactions

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