Q: A student dissolves 5.00 g of NaCl in enough water to make 250 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

$$M = \frac{5.00}{58.44} \div 0.250 = 0.342\ \text{M}$$

Q: A sample of gas occupies 2.00 L at 1.00 atm and 300 K. What will its volume be at 2.00 atm and 300 K?

$$V_2$$ = \frac{2.00 \times 1.00}{2.00} = 1.00\ \text{L}$$

Q: Which of the following best explains why $$\text{H}_2O$$ has a higher boiling point than $$\text{CH}_4$$?

$$\text{H}_2O$$ forms hydrogen bonds, which are stronger than dispersion forces.

Q: A 0.500 mol sample of $$\text{O}_2$$ gas is placed in a 10.0 L container at 300 K. What is the pressure of the gas? ($$R = 0.0821\ \text{L} \cdot \text{atm} / \text{mol} \cdot \text{K})$$

$$P = \frac{0.500 \times 300 \times 0.0821}{10.0} = 1.23\ \text{atm}$$

Q: Which of the following is the correct formula for calculating density?

$$\text{Density} = \frac{\text{Mass}}{\text{Volume}}$$

Question 1

Which of the following statements best describes a heterogeneous mixture?

Accepted Answer

It contains visibly different parts or phases, such as sand in water.

Question 2

A student dissolves 5.00 g of NaCl in enough water to make 250 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$M = \frac{5.00}{58.44} \div 0.250 = 0.342\ 	ext{M}$$

Question 3

Which of the following ions has the same electron configuration as Ne ($$1s^2$$ $$2s^2$$ $$2p^6$$)?

Accepted Answer

$$	ext{Na}^+$$

Question 4

Which of the following correctly describes the trend in atomic radius across a period from left to right?

Accepted Answer

Atomic radius decreases due to increasing effective nuclear charge.

Question 5

Which of the following compounds is most likely to be ionic?

Accepted Answer

$$	ext{NaCl}$$

Question 6

What is the formal charge on the central atom in $$	ext{NO}_3^- ($$nitrate ion)?

Accepted Answer

$$0$$

Question 7

Which of the following molecules has a trigonal planar geometry?

Accepted Answer

$$	ext{BF}_3$$

Question 8

A sample of gas occupies 2.00 L at 1.00 atm and 300 K. What will its volume be at 2.00 atm and 300 K?

Accepted Answer

$$V_2$$ = \frac{2.00 	imes 1.00}{2.00} = 1.00\ 	ext{L}$$

Question 9

Which of the following best explains why $$	ext{H}_2O$$ has a higher boiling point than $$	ext{CH}_4$$?

Accepted Answer

$$	ext{H}_2O$$ forms hydrogen bonds, which are stronger than dispersion forces.

Question 10

Which of the following is the correct electron configuration for $$	ext{Fe}^{3+}$$?

Accepted Answer

$$[	ext{Ar}]\ 3d^5$

Question 11

Which of the following best describes the effect of increasing molecular weight on the magnitude of dispersion forces?

Accepted Answer

Dispersion forces increase as molecular weight increases.

Question 12

A 0.500 mol sample of $$	ext{O}_2$$ gas is placed in a 10.0 L container at 300 K. What is the pressure of the gas? ($$R = 0.0821\ 	ext{L} \cdot 	ext{atm} / 	ext{mol} \cdot 	ext{K})$$

Accepted Answer

$$P = \frac{0.500 	imes 300 	imes 0.0821}{10.0} = 1.23\ 	ext{atm}$$

Question 13

Which of the following is true about the kinetic molecular theory of gases?

Accepted Answer

The average kinetic energy of gas molecules is proportional to the temperature in Kelvin.

Question 14

Which of the following molecules is expected to have the highest dipole moment?

Accepted Answer

$$	ext{NH}_3$$

Question 15

Which of the following best describes the effect of hydrogen bonding on boiling point?

Accepted Answer

Hydrogen bonding raises the boiling point of a substance.

Question 16

Which of the following is the correct formula for calculating density?

Accepted Answer

$$	ext{Density} = \frac{	ext{Mass}}{	ext{Volume}}$$

Question 17

Which of the following is the correct expression for Graham's Law of Effusion?

Accepted Answer

$$\frac{	ext{Rate}_1}{	ext{Rate}_2} = \sqrt{\frac{M_2$}{M_1$}}$$

Question 18

Which of the following best explains why $$	ext{Cl}_2$$ has a higher boiling point than $$	ext{F}_2$$?

Accepted Answer

$$	ext{Cl}_2$$ has a higher molecular weight, leading to stronger dispersion forces.

Question 19

Which of the following is the correct formula for calculating percent yield in a chemical reaction?

Accepted Answer

$$	ext{Percent Yield} = \frac{	ext{Actual Yield}}{	ext{Theoretical Yield}} 	imes 100\%$$

General Chemistry I: Comprehensive Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard