Chapter 2 - The Chemistry of Biology

Question 1

An Element is a substance that …

Answer 1

cannot be broken down into any other substance.

Question 2

What is an atom ?

Answer 2

Matter that cannot be subdivided any further without loosing its essential property.

Question 3

What is the center of an atom and what does it contain ?

Answer 3

A central nucleus and contains protons, neutrons. Surrounded by electrons.

Question 4

What are protons, neutrons, and electrons ?

Answer 4

Sub atomic particles.

Question 5

What is the Atomic number ?

Answer 5

The number of Protons.

Question 6

What are Isotopes ?

Answer 6

Atoms with the same atomic number but different atomic masses.

Question 7

How do you find the atomic mass ?

Answer 7

Protons + Neutrons.

Question 8

What are Radioactive Atoms ?

Answer 8

Atomic nuclei that are not stable and break down spontaneously.

Question 9

What are the “Big Four” Elements in our body ?

Answer 9

Oxygen, Hydrogen, Carbon, and Nitrogen.

Question 10

What do the Electrons do ?

Answer 10

determine whether, and HOW, the atom will bond with other atoms.

Question 11

How man electrons can the 1st shell contain ?

Answer 11

2

Question 12

How many electrons can the 2nd shell contain ?

Answer 12

8

Question 13

What do Electrons do ?

Answer 13

Electrons determine whether, and HOW, the atom will bond with other atoms.

Question 14

When the electron shell is filled to capacity, then the shell is …

Answer 14

Stable.

Question 15

Carbon can share up to _ different atoms

Answer 15

4

Question 16

Carbon is very versatile and mostly shares with _, _, _, and _ .

Answer 16

Oxygen, Hydrogen, Nitrogen, and other carbon.

Question 17

Ions are …

Answer 17

Charged atoms.

Question 18

If an ion loses one or more atoms it is _ charged.

Answer 18

Positively

Question 19

If an ion adds electrons it is _ charged.

Answer 19

Negatively

Question 20

The chemical characteristics of an atom depend on what ?

Answer 20

The number of electrons in OUTER most shell.

Question 21

Molecules are …

Answer 21

groups of atoms held together by bonds.

Question 22

Bond Energy is dependent …

Answer 22

Upon the atoms involved.

Question 23

Chemical reactions involve doing what to bonds?

Answer 23

The forming and breaking

Question 24

How are molecules illistarted ?

Answer 24

Lewis model, Ball and Stick model, and Space filling model.

Question 25

Covalent bonds are two atoms sharing _ .

Answer 25

electrons.

Question 26

What are the two types of Covalent Bonds ?

Answer 26

Single and Double.

Question 27

Ionic Bonds are attractions that …

Answer 27

hold together two oppositely charged ions.

Question 28

Are Ionic Bonds Neutral ?

Answer 28

Yes

Question 29

Hydrogen Bonds , bond …

Answer 29

molecules together.

Question 30

Hydrogen Bonds form between a slightly _ _ atom and a slightly _ atom in the other.

Answer 30

Positively Hydrogen ; Negative

Question 31

Are Hydrogen Bonds weaker or stronger than Covalent and Ionic Bonds ?

Answer 31

Weaker.

Question 32

Hydrogen Bonds make water …

Answer 32

Cohesive.

Question 33

The pH of a fluid is a measure of …

Answer 33

How acidic or basic the solution is.

Question 34

Pure water has equal _ and _.

Answer 34

H+; O+

Question 35

The amount of H+ in a solution is called…

Answer 35

pH

Question 36

Acids have a pH _ than 7.0.

Answer 36

Lower.

Question 37

Bases have a pH _ than 7.0.

Answer 37

Higher.

Question 38

Bases have a bitter taste and a _ /_ feel.

Answer 38

Slippery/Soapy.

Question 39

The lower the pH, the higher the_ .

Answer 39

Acidity.

Question 40

Buffers do what to the pH ?

Answer 40

Resist change by absorbing or releasing H+.