Q: A 550 g sample of chromium(III) oxide (Cr$$_2O$_3) $$contains 376 g of Cr. How many grams of Cr are in a 212 g sample of Cr$$_2O$_3$$?

$$\frac{376}{550} \times 212 = 145\ \mathrm{g}$$

Q: How many atoms are in 0.68 moles of zinc?

$$0.68 \times 6.02 \times 10$$^{23}$$ = 4.09 \times 10$$^{23}$$ atoms

Q: A rectangular solid has edge lengths 8.2 cm, 5.1 cm, and 4.7 cm. What is its volume?

$$8.2 \times 5.1 \times 4.7 = 196.8\ \mathrm{cm^3$}$$

Q: Which of the following statements about the mole is correct?

1 mole contains $$6.02 \times 10$$^{23}$$ particles.

Q: A sample of butane (C$$_4H$_{10}) $$contains 288 g carbon and 60 g hydrogen. What is the percent by mass of hydrogen in butane?

$$\frac{60}{288+60} \times 100 = 17.3\%$$

Question 1

Which of the following best describes an element?

Accepted Answer

A substance that contains only one type of atom and cannot be separated by physical or chemical means.

Question 2

Which property is classified as intensive?

Accepted Answer

Density

Question 3

A sample of lead (Pb) has a mass of 22.7 g and a volume of 2.0 cm$$^3. $$What is the density of the sample?

Accepted Answer

$$\frac{22.7}{2.0} = 11.35\ \mathrm{g/cm^3$}$$

Question 4

Which of the following is a chemical property?

Accepted Answer

Reactivity with water

Question 5

Which separation technique would be most effective for separating a mixture of sand and salt water?

Accepted Answer

Filtration

Question 6

A 550 g sample of chromium(III) oxide (Cr$$_2O$_3) $$contains 376 g of Cr. How many grams of Cr are in a 212 g sample of Cr$$_2O$_3$$?

Accepted Answer

$$\frac{376}{550} 	imes 212 = 145\ \mathrm{g}$$

Question 7

Which of the following is a homogeneous mixture?

Accepted Answer

Salt water

Question 8

Which statement about compounds is correct?

Accepted Answer

Compounds have properties different from those of their constituent elements.

Question 9

How many atoms are in 0.68 moles of zinc?

Accepted Answer

$$0.68 	imes 6.02 	imes 10$$^{23}$$ = 4.09 	imes 10$$^{23}$$ atoms

Question 10

Which of the following changes is exothermic?

Accepted Answer

Water freezing

Question 11

A rectangular solid has edge lengths 8.2 cm, 5.1 cm, and 4.7 cm. What is its volume?

Accepted Answer

$$8.2 	imes 5.1 	imes 4.7 = 196.8\ \mathrm{cm^3$}$$

Question 12

Which of the following is an example of a physical change?

Accepted Answer

Ice melting

Question 13

Which of the following statements about the mole is correct?

Accepted Answer

1 mole contains $$6.02 	imes 10$$^{23}$$ particles.

Question 14

Which of the following is an example of an allotrope?

Accepted Answer

Diamond and graphite (forms of carbon)

Question 15

A sample of butane (C$$_4H$_{10}) $$contains 288 g carbon and 60 g hydrogen. What is the percent by mass of hydrogen in butane?

Accepted Answer

$$\frac{60}{288+60} 	imes 100 = 17.3\%$$

Question 16

Which of the following is a diatomic element?

Accepted Answer

O$$_2$$

Question 17

Which of the following is NOT a method for separating mixtures?

Accepted Answer

Electrolysis

Question 18

Which statement best describes a heterogeneous mixture?

Accepted Answer

A mixture with different composition and properties in the same sample; unevenly mixed.

Question 19

Which of the following is an extensive property?

Accepted Answer

Mass

Question 20

Which process is an example of the Law of Conservation of Energy?

Accepted Answer

Combustion of acetylene: $$2\ \mathrm{H_2$} + \mathrm{O_2$} \rightarrow 2\ \mathrm{H_2O}$$

Fundamental Concepts in General Chemistry: Matter, Classification, Properties, and the Mole

Study Guide - Practice Questions

Study Guide - Flashcards