Properties & Changes (Ch. 21) Test

5 Characteristics of Chemical Changes

1) Precipitate 2) Gas is produced 3) New Taste 4) New Smell 5) New color that is NOT a blend

Most chemists focus on: A) applied research to provide us with new technology. B) basic research to provide us with new technology. C) applied research to learn more about our universe. D) basic research to learn more about our universe data.

A

What does the bohr modle resemble?

A solar system

Are atoms made of molecules or are molecules made of atoms? A) Atoms are made of molecules. B) Molecules are made of atoms.

B

The Physical Properties of a compound are: A) a blend of the physical properties of the elements from which it is made. B) uniquely different from the physical properties of the elements from which it is made. C) a result of the physical properties of the elements from which it is made. D) the same as the physical properties of the elements from which it is made.

B

The circles in the boxes shown above represent the submicroscopic particles of a material in its three phases. From left to right these are A) solid, liquid, and gas. B) liquid, solid, and gas. C) gas, solid, and liquid. D) gas, liquid, and solid.

B

The reaction represented in the following diagrams is best described by which of the following balanced equations?: A) 12 A + 5 B + 5 C ---> 4 A3B + 2 C2 + BC B) A + BC ---> AB + C C) 6 A + 2 BC ---> 2 A3B + C2 D) 12 A + 5 BC ---> 4 A3B + 2 C2 + BC E) 12 A + 4 BC ---> (A3B)4 + 2 C2

B

How Does Chemistry Differ From Biology?

Biology deals exclusively with living things, while chemistry deals with living and nonliving.

During a chemical change: A) the physical properties of a substance change. B) molecules change how they are oriented relative to one another. C) atoms change partners to form a new material. D) there is typically less energy involved than in a physical change.

C

In The Previous Question, Which Reactant Remained Unreacted? A) a B) b C) c D) d E) None.

C

13. In the boxes shown above, each solid circle represents an atom of the same element. How many different types of molecules are depicted in the above transformation? A) 1 B) 2 C) 3 D) 4 E) 5

D

When Are Electrical Charges Strongest?

Electrical charges are strongest when the charges are closest together

What Binds Atomes Together?

Electrical forces bind atoms together

How do Elements Differ from Compounds?

Elements only have one type of atoms, while compounds have multiple types of atoms

T or F: Chemical equations are balanced by modifying the subscript of chemical formula data.

False: Chemical equations are balanced by modifying the coefficient of chemical formula data.

T or F: Molecules are of the microscopic realm.

False: Molecules are of the submicroscopic realm.

T or F: Sodium chloride is toxic because of the sodium metal it contains.

False: Sodium chloride is not toxic even though it contains sodium metal

T or F: The freezing of water is an example of a chemical change.

False: The freezing of water is an example of a physical change.

State the Law of Conservation of Mass

Mass cannot be created or destroyed

T or F: A compound is made of atoms from different elements.

True: A compound is made of atoms from different elements.