Question 1

Which of the following best describes the field of chemistry?

Accepted Answer

The science dealing with the composition of matter and the changes in composition that matter undergoes.

Question 2

A chemist is analyzing a sample of air. Which approach is the chemist using when considering the behavior of individual molecules within the air?

Accepted Answer

Microscopic approach

Question 3

Which of the following is the correct sequence of steps in the scientific method?

Accepted Answer

Observation, hypothesis, experiment, theory, law

Question 4

A student proposes that increasing the temperature of a solution will increase the rate at which sugar dissolves. This statement is an example of which part of the scientific method?

Accepted Answer

Hypothesis

Question 5

Which of the following statements is a scientific law?

Accepted Answer

All gases expand when heated.

Question 6

You are given 12 hydrogen atoms and 7 oxygen atoms. According to the formula for water, $$\mathrm{H_2O}$$, how many water molecules can you make?

Accepted Answer

6

Question 7

Which of the following is NOT a characteristic of matter?

Accepted Answer

Can be seen with the naked eye

Question 8

Which state of matter has a definite volume but no definite shape?

Accepted Answer

Liquid

Question 9

Which of the following best describes a crystalline solid?

Accepted Answer

Particles are arranged in a regular, repeating, three-dimensional geometric pattern

Question 10

A mixture of iron filings and sulfur can be separated by using a magnet. What type of mixture is this?

Accepted Answer

Heterogeneous mixture

Question 11

Which of the following is a homogeneous mixture?

Accepted Answer

Air

Question 12

Which of the following is a pure substance?

Accepted Answer

Gold

Question 13

Which of the following best describes a gas?

Accepted Answer

Indefinite shape and volume

Question 14

A solution of salt dissolved in water is an example of:

Accepted Answer

A homogeneous mixture

Question 15

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

Accepted Answer

Melting of ice

Question 16

Which of the following statements about mixtures is correct?

Accepted Answer

The components of a mixture can be separated by physical means.

Question 17

A student observes that a candle burns more brightly in pure oxygen than in air. This observation leads to the hypothesis that oxygen supports combustion. Which is the observation?

Accepted Answer

A candle burns more brightly in pure oxygen than in air.

Question 18

Which of the following is an example of a compound?

Accepted Answer

Table salt ($$\mathrm{NaCl})$$

Question 19

Which of the following best describes an amorphous solid?

Accepted Answer

Has no regular repeating pattern

Question 20

A bottle contains both solid and liquid acetic acid at 16.7 °C, and a strong vinegar-like odor is noticeable immediately after opening. How many phases must be present in the bottle?

Accepted Answer

Three

Introduction to Chemistry: The Chemical World, Scientific Method, and Classification of Matter

Guida di studio - Domande di pratica

Study guide - Flashcard