Q: A sample contains 0.50 mol of NaCl. What is the mass of NaCl in the sample? (Molar mass of NaCl = 58.44 g/mol)

$$0.50 \times 58.44 = 29.22 g$$

Q: A chemical reaction has the following rate law: $$\text{Rate} = k[A]^2[B]. If $$the concentration of A is doubled and B is tripled, by what factor does the rate increase?

The rate increases by a factor of $$2^2$$ \times 3 = 12$$

Q: A gas sample at 1.00 atm and 273 K occupies 22.4 L. If the pressure is doubled and the temperature is halved, what is the new volume?

$$V_2$$ = $$V_1$$ \times \frac{$$P_1$$}{$$P_2$$} \times \frac{$$T_2$$}{$$T_1$$} = 22.4 \times \frac{1.00}{2.00} \times \frac{136.5}{273} = 5.6$$ L

Question 1

Which of the following statements best describes the difference between covalent and ionic bonds?

Accepted Answer

Covalent bonds involve the sharing of electrons between atoms, while ionic bonds involve the transfer of electrons from one atom to another.

Question 2

A sample contains 0.50 mol of NaCl. What is the mass of NaCl in the sample? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$0.50 	imes 58.44 = 29.22 g$$

Question 3

Which of the following best explains why water has a higher boiling point than methane?

Accepted Answer

Water forms hydrogen bonds, which are stronger than the London dispersion forces present in methane.

Question 4

Which equation correctly represents the relationship between energy, frequency, and Planck's constant?

Accepted Answer

$$E = h 
u$$

Question 5

A chemical reaction has the following rate law: $$	ext{Rate} = k[A]^2[B]. If $$the concentration of A is doubled and B is tripled, by what factor does the rate increase?

Accepted Answer

The rate increases by a factor of $$2^2$$ 	imes 3 = 12$$

Question 6

Which of the following is the correct balanced equation for the combustion of propane ($$C_3H_8) in $$oxygen?

Accepted Answer

$$C_3H_8 + 5O_2 \rightarrow 3CO_2 + 4H_2O$$

Question 7

Which statement about Le Chatelier's Principle is correct?

Accepted Answer

If a system at equilibrium is disturbed, the system will shift to minimize the disturbance and restore equilibrium.

Question 8

Which of the following is the correct formula for calculating the pH of a solution given the hydrogen ion concentration $$[H^+]$$?

Accepted Answer

$$	ext{pH} = -\log [H^+]$$

Question 9

A solution is prepared by dissolving 0.1 mol of acetic acid ($$CH_3COOH) in $$water. Which of the following best describes the solution?

Accepted Answer

It is a weak acid and will partially ionize in water.

Question 10

Which of the following best describes the process of oxidation in a redox reaction?

Accepted Answer

Oxidation is the loss of electrons by a species.

Question 11

Which of the following elements has the highest electronegativity?

Accepted Answer

Fluorine

Question 12

A gas sample at 1.00 atm and 273 K occupies 22.4 L. If the pressure is doubled and the temperature is halved, what is the new volume?

Accepted Answer

$$V_2$$ = $$V_1$$ 	imes \frac{$$P_1$$}{$$P_2$$} 	imes \frac{$$T_2$$}{$$T_1$$} = 22.4 	imes \frac{1.00}{2.00} 	imes \frac{136.5}{273} = 5.6$$ L

Question 13

Which of the following is a correct statement about metallic bonding?

Accepted Answer

Metallic bonding involves a 'sea of electrons' that are delocalized over a lattice of metal cations.

Question 14

Which of the following is the correct formula for calculating the enthalpy change ($$\Delta H) of a $$reaction using bond energies?

Accepted Answer

$$\Delta H = \sum 	ext{Bond energies of products} - \sum 	ext{Bond energies of reactants}$$

Question 15

Which of the following is the correct electron configuration for a neutral oxygen atom?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^4$$

Question 16

Which of the following is a correct statement about equilibrium constants ($$K$$)?

Accepted Answer

The equilibrium constant $$K is $$only affected by changes in temperature.

Question 17

Which of the following is the correct formula for calculating the molarity ($$M) of a $$solution?

Accepted Answer

$$M = \frac{	ext{moles of solute}}{	ext{liters of solution}}$$

Question 18

Which of the following hydrocarbons is an alkene?

Accepted Answer

Ethene ($$C_2H_4)$$

Question 19

Which of the following is the correct cell notation for a galvanic cell with zinc and copper electrodes?

Accepted Answer

$$Zn(s) | Zn$$^{2+}$$(aq) || Cu$$^{2+}$$(aq) | Cu(s)$$

General Chemistry I: Course Outline and Key Topics

Guida di studio - Domande di pratica

Study guide - Flashcard