Question 1

Which of the following statements best describes the organization of subatomic particles in an atom according to modern atomic theory?

Accepted Answer

Protons and neutrons are tightly packed in a small nucleus. Electrons occupy the space outside the nucleus.

Question 2

A student dissolves 100.0 g of CoCl$$_2 in $$enough water to make 5.50 L of solution. What is the molarity of the resulting cobalt(II) chloride solution? (Molar mass of CoCl$$_2 = 129.84 g/$$mol)

Accepted Answer

$$0.154\ \mathrm{mol/L}$$

Question 3

Which of the following reactions is NOT balanced?

Accepted Answer

$$\mathrm{SF}_4 + 3\ \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{H}_2\mathrm{SO}_3 + 4\ \mathrm{HF}$$

Question 4

According to Arrhenius, an acid and a base will react to always give:

Accepted Answer

a salt plus water.

Question 5

Which of the following compounds would be insoluble in water based on solubility rules?

Accepted Answer

$$\mathrm{CaCO}_3$$

Question 6

A sample of boron contains two isotopes: boron-10 (10.01 amu, 20%) and boron-11 (11.00 amu, 80%). What is the average atomic mass of boron?

Accepted Answer

$$10.81\ \mathrm{amu}$$

Question 7

What is the oxidation number of bismuth in $$\mathrm{Bi}_2\mathrm{O}_7$$?

Accepted Answer

$$+6$$

Question 8

Which of the following is a correct net ionic equation for the reaction between $$\mathrm{Sr(NO}_3)_2$$ and $$\mathrm{K}_2\mathrm{SO}_4$$?

Accepted Answer

$$\mathrm{Sr}^{2+} (aq) + \mathrm{SO}_4$$^{2-}$$ (aq) \rightarrow \mathrm{SrSO}_4 (s)$$

Question 9

A 0.256 M thiosulfate solution is used to titrate 1.50 L of 0.0731 M iodine solution according to the reaction:

$$\mathrm{I}_2 (aq) + 2\ \mathrm{S}_2\mathrm{O}_3$$^{2-}$$ (aq) \rightarrow 2\ \mathrm{I}^- (aq) + \mathrm{S}_4\mathrm{O}_6$$^{2-}$$ (aq)$$

What volume of thiosulfate solution is required for complete reaction?

Accepted Answer

$$0.857\ \mathrm{L}$$

Question 10

Which of the following is the correct empirical formula for a compound that is 54.54% C, 9.09% H, and 36.36% O by mass?

Accepted Answer

$$\mathrm{C}_2\mathrm{H}_4\mathrm{O}$$

Question 11

Which of the following is a postulate of Dalton's atomic theory that has been modified in light of later discoveries?

Accepted Answer

Atoms of a given element are identical.

Question 12

A gas sample has a pressure of 760 mmHg, a volume of 2.00 L, and a temperature of 273 K. How many moles of gas are present? ($$R = 0.08206\ \mathrm{L\cdot atm\cdot $$mol^{-1}$$\cdot K$$^{-1}$$})$$

Accepted Answer

$$0.0892\ \mathrm{mol}$$

Question 13

Which of the following is the correct net ionic equation for the reaction of hydrochloric acid with sodium hydroxide?

Accepted Answer

$$\mathrm{H}^+ (aq) + \mathrm{OH}^- (aq) \rightarrow \mathrm{H}_2\mathrm{O} (l)$$

Question 14

A 1.00 L sample of a gas at 25$$^\circC $$and 1.00 atm is compressed to 0.500 L and heated to 50$$^\circC. $$What is the final pressure of the gas? (Assume ideal gas behavior.)

Accepted Answer

$$2.12\ \mathrm{atm}$$

Question 15

Which of the following is the correct formula for lithium permanganate?

Accepted Answer

$$\mathrm{LiMnO}_4$$

Question 16

What is the percent composition by mass of carbon in DEET ($$\mathrm{C}_{12}\mathrm{H}_{17}\mathrm{NO}$$, molar mass = 191 g/mol)?

Accepted Answer

$$60.2\%$$

Question 17

When the equation $$\mathrm{C}_3\mathrm{H}_8 + \mathrm{O}_2 \rightarrow \mathrm{CO}_2 + \mathrm{H}_2\mathrm{O} is $$balanced with the lowest whole number coefficients, what is the coefficient of $$\mathrm{O}_2$$?

Accepted Answer

$$5$$

Question 18

Which of the following best describes a redox reaction?

Accepted Answer

A reaction in which electrons are transferred between species.

Question 19

Which of the following is the correct molarity for a solution made by diluting 0.450 L of 0.450 M K$$_2CO$_3 to a $$final volume of 0.315 L?

Accepted Answer

$$0.635\ \mathrm{M}$$

General Chemistry Study Guide: Constants, Units, Atomic Theory, Chemical Reactions, and Problem Solving

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