Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements in fixed, definite proportions.

Question 2

Which statement about the states of matter is correct?

Accepted Answer

In a liquid, atoms or molecules are closely packed but can move relative to each other.

Question 3

A sample of water is decomposed into 16.0 g of oxygen and 2.0 g of hydrogen. What is the mass ratio of oxygen to hydrogen in water?

Accepted Answer

$$ \frac{16.0\ g\ O}{2.0\ g\ H} = 8.0 $$

Question 4

Which of the following is an example of a homogeneous mixture?

Accepted Answer

Sweetened tea.

Question 5

Which law states that in a chemical reaction, matter is neither created nor destroyed?

Accepted Answer

Law of conservation of mass

Question 6

A scientist observes that all samples of carbon dioxide contain the same ratio of oxygen to carbon by mass. Which law does this observation support?

Accepted Answer

Law of definite proportions

Question 7

Which of the following best explains the difference between a law and a theory?

Accepted Answer

A law summarizes a series of related observations, while a theory gives the underlying reasons for them.

Question 8

Which of the following is NOT a characteristic of a good scientific hypothesis?

Accepted Answer

It can never be proven wrong by any experiment.

Question 9

Which of the following statements about atoms and molecules is correct?

Accepted Answer

Molecules are formed when two or more atoms bond in specific geometric arrangements.

Question 10

Which of the following is a heterogeneous mixture?

Accepted Answer

Salad with tomatoes and lettuce

Question 11

Which of the following is an example of quantifiable scientific data?

Accepted Answer

The mass of the sample is 12.5 g.

Question 12

Which of the following best describes the state of matter in which atoms or molecules are far apart and compressible?

Accepted Answer

Gas

Question 13

Which of the following is a pure substance?

Accepted Answer

Oxygen gas ($$ O_2$ )$$

Question 14

Which of the following statements about Dalton’s atomic theory is correct?

Accepted Answer

Atoms combine in simple, whole-number ratios to form compounds.

Question 15

A sample of compound X contains 12 g of carbon and 32 g of oxygen. What is the mass ratio of oxygen to carbon in this compound?

Accepted Answer

$$ \frac{32\ g\ O}{12\ g\ C} = 2.67 $$

Question 16

Which of the following is an example of a chemical property?

Accepted Answer

Iron reacts with oxygen to form rust.

Question 17

Which of the following best describes a mixture?

Accepted Answer

A substance composed of two or more components in variable proportions.

Question 18

Which of the following is a correct statement about the scientific method?

Accepted Answer

It involves observation, hypothesis formation, experimentation, and formulation of laws and theories.

Question 19

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

Accepted Answer

Dissolving sugar in water

Question 20

Which of the following best describes the law of multiple proportions?

Accepted Answer

When two elements form two different compounds, the masses of one element that combine with a fixed mass of the other are in a ratio of small whole numbers.

Atoms and the Classification of Matter: Chapter 1 Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards