Question 1

Which of the following best describes chemistry as presented in the study materials?

Accepted Answer

The study of matter and the transformations it can undergo.

Question 2

A chemical property is best defined as:

Accepted Answer

A property that describes the tendency of a substance to transform into a new substance.

Question 3

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

Accepted Answer

Rusting of iron.

Question 4

When oxygen ($$O_2) is $$transformed into ozone ($$O_3$$), what type of change occurs?

Accepted Answer

Chemical change.

Question 5

Which statement correctly distinguishes between an element and a compound?

Accepted Answer

An element is made of only one kind of atom, while a compound consists of atoms of different elements.

Question 6

Which of the following is a correct chemical formula for a compound?

Accepted Answer

$$NaCl$$

Question 7

What is the name of the compound with the formula $$CBr_4$$?

Accepted Answer

Carbon tetrabromide.

Question 8

Which of the following is a physical change?

Accepted Answer

Melting a piece of solid gold.

Question 9

Tarnishing a piece of silver is considered a chemical change because:

Accepted Answer

Silver transforms into silver sulfide, forming a new substance.

Question 10

Which prefix is used to indicate two atoms of an element in a compound's name?

Accepted Answer

Di-

Question 11

What is the correct name for the compound $$CO_2$$?

Accepted Answer

Carbon dioxide.

Question 12

Which of the following statements about compounds is true?

Accepted Answer

Compounds have properties uniquely different from the elements from which they are made.

Question 13

A single grain of sand contains about 125 million trillion atoms. Which scientific notation correctly represents this number?

Accepted Answer

$$1.25 	imes 10$$^{20}$$

Question 14

Which of the following is the correct chemical formula for water?

Accepted Answer

$$H_2O$$

Question 15

Which guideline is used when naming a compound formed from two elements?

Accepted Answer

Start with the element farthest to the left in the periodic table and add the suffix -ide to the element on the right.

Question 16

Which of the following is an example of a compound with a common name used for convenience?

Accepted Answer

Dihydrogen monoxide (water).

Question 17

Which of the following best explains why both physical and chemical changes result in a change in physical appearance?

Accepted Answer

Both types of changes alter the arrangement or state of matter, affecting how it looks.

Question 18

If you combine sodium ($$Na) $$and chlorine ($$Cl$$), what compound do you form and what is its formula?

Accepted Answer

Sodium chloride, $$NaCl$$

Question 19

Which of the following is a correct example of using prefixes to remove ambiguity in compound naming?

Accepted Answer

Carbon dioxide for $$CO_2$$

Question 20

Which of the following is NOT a chemical property?

Accepted Answer

The melting point of ice.

Elements of Chemistry: Physical and Chemical Properties, Elements, and Compounds

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