Unit #9 Compounds and Molecules

Question 1

What is the smallest unit of an element?

Answer 1

An atom

Question 2

What is matter made up of only one type of atom?

Answer 2

An element

Question 3

What is a compound?

Answer 3

Two or more elements chemically combined

Question 4

What is a molecule?

Answer 4

The smallest unit of a compound

Question 5

What is a chemical bond?

Answer 5

A bond that holds two atoms together in a compound

Question 6

What is a chemical formula?

Answer 6

Explains the type and number of elements in a compound

Question 7

What is an ionic bond?

Answer 7

A chemical bond that occurs when one atom gives an electron to another atom

Question 8

What is a covalent bond?

Answer 8

A chemical bond that occurs when two atoms share an electron

Question 9

What is a valence electron?

Answer 9

An electron in the outer shell of an atom

Question 10

What is an ion?

Answer 10

A charged atom that has gained or lost electrons

Question 11

What is a cation?

Answer 11

An atom with a positive charge

Question 12

What is a positive ion (cation)?

Answer 12

When an atom loses one or more electrons

Question 13

What is a negative ion (anion)?

Answer 13

When an atom gains one or more electrons

Question 14

What is the chemical formula for water?

Answer 14

H20

Question 15

What is the chemical formula for Carbon Dioxide?

Answer 15

CO2

Question 16

What is C6H12O6?

Answer 16

Sugar (Glucose)

Question 17

What is the chemical formula for stomach acid?

Answer 17

HCl (Hydrogen Chloride)

Question 18

What is the chemical formula Limestone (Calcium Carbonate)?

Answer 18

CaCO3

Question 19

What is the chemical formula for rust (Di-iron Tri-Oxide)?

Answer 19

Fe2O3

Question 20

What is the chemical formula for table salt (Sodium Chloride)?

Answer 20

NaCl

Question 21

What is the chemical formula for sand (Silicon Dioxide)?

Answer 21

SiO2

Question 22

What do atoms lose or gain electrons?

Answer 22

To become stable (fill their outer electron shell).

Question 23

Why are Na and Cl very unstable?

Answer 23

Because their outer electron shells are not completely full

Question 24

What do elements like Na and Cl combine?

Answer 24

To make stable compounds by filling their outer shells

Question 25

How many atoms are in H20?

Answer 25

3 atoms

Question 26

How many atoms are in Ca(OH)2?

Answer 26

5 atoms

Question 27

What is a diatomic molecule?

Answer 27

Occurs when two atoms of the same element bond together

Question 28

Give examples of diatomic gases.

Answer 28

H2, O2, and N2

Question 29

What planet contains a great amount of iron dioxide?

Answer 29

The surface of Mars

Question 30

What is a mixture?

Answer 30

Two or more different substances which are mixed but are not combined chemically

Question 31

Give an example of a mixture.

Answer 31

Tap Water

Question 32

What is salt water?

Answer 32

A solution containing NaCl + H2O

Question 33

Give an example of a Covalent Bond.

Answer 33

H2O

Question 34

Give an example of a Ionic Bond.

Answer 34

NaCl

Question 35

What is a mixture?

Answer 35

Two or more elements that are mixed together but not chemically combined

Question 36

What is the compound found in sand, dirt, and rocks?

Answer 36

Silicon Dioxide (SiO2)

Question 37

What is the compound that humans often eat to obtain energy?

Answer 37

Glucose (C6H12O6)

Question 38

What is electrolysis?

Answer 38

When electricity is used to separate compounds

Question 39

What gas is very explosive and not used in blimps today?

Answer 39

Hydrogen Gas

Question 40

Name some physical properties.

Answer 40

Size, color, and luster

Question 41

What are the noble gases?

Answer 41

Very stable elements (Helium and Neon)?

Question 42

Is the state of a substance (solid, liquid, or gas) a physical or chemical property?

Answer 42

Physical property

Question 43

What happens if a Mg atom loses two electrons?

Answer 43

It becomes a Mg+2 ion.

Question 44

What makes up air on Earth?

Answer 44

A mixture of N2, O2, and several other gases