Chapter 2- Essential Chemistry For Biology

Question 0

What helps maintain healthy teeth?

Answer 0

Fluoride

Question 1

What is a Common Ingredient in Earths Crust?

Answer 1

Fluoride

Question 2

How does Fluoride prevent Cavities in the Teeth?

Answer 2

1. By affecting the metabolism of oral bacteria

2. Promoting the replacement of lost minerals on the tooth surface

Question 3

What is matter?

Answer 3

Matter is anything that occupies space and has mass

Question 4

What 3 forms is matter found on earth?

Answer 4

1. Liquid
2. Solid
3. Gas

Question 5

What is matter Composed of?

Answer 5

Chemical elements

Question 6

How many naturally occurring elements are there on earth?

Answer 6

92 (all are listed on the periodic table)

Question 7

How many elements are essential to life?

Answer 7

25

Question 8

What 4 elements make up 96% of the human body?

Answer 8

1. Oxygen
2. Carbon
3. Hydrogen
4. Nitrogen

Question 9

What occurs in smaller amounts and if essential for life?

Answer 9

Trace elements

Question 10

What can an iodine deficiency cause?

Answer 10

Goiter

Question 11

Elements can be combined to form what?

Answer 11

Compounds

Question 12

What is a Compound?

Answer 12

Compounds are substances that contain 2 or more elements in a mixed ratio

Question 13

What are 2 common compounds?

Answer 13

NaCI (table salt)

h2o (water)

Question 14

What does each element consist of?

Answer 14

Atoms

Question 15

What is an atom?

Answer 15

A atom is the smallest unit of matter that still retains the property of an element.

Question 16

What are 3 things subatomic particles are atoms composed of?

Answer 16

• Protons (positive)
• Electrons (negative)
• Neuron (electrically Neutral)

Question 17

Most Atoms have protons and neurons packed tightly into what?

Answer 17

The Neuclis

Question 18

What is the Atoms Central Core?

Answer 18

The Nueclis

Question 19

What orbits the Neuclis?

Answer 19

Electrons

Question 20

What is the sum of the number or protons and Neurons called?

Answer 20

Mass Numbers

Question 21

What is measurement of the amount of matter in an object?

Answer 21

Mass

Question 22

What do Atomic Numbers determine?

Answer 22

They determine which element is which

Question 23

What is an alternate mass form of an element? And Has the same number I protons and electrons but have different number of Neurons?

Answer 23

Isotope

Question 24

What decays and gives off particles and energy?

Answer 24

The Neuclis of Radioactive Isotopes

Question 25

What can Radioactive Isotopes be used for?

Answer 25

Medical research and Medicine Used to determine the date of atoms in living organisms Use in a petscan to diagnose heart disorders and some cancer

Question 26

What can happen if you are exposed to radioactive isotopes?

Answer 26

It can damage the DNA

Question 27

Chemical reaction normally result is what?

Answer 27

Atoms staying close together Atoms being held together by chemical bonds

Question 28

What is an ionic bond?

Answer 28

It's when an atom loses or gains and electrons and transfers other electrons

Question 29

Atoms are held together by covalent bonds are called what?

Answer 29

Molecules

Question 30

What charges atoms?

Answer 30

Ions

Question 31

The number is covalent bonds an atoms can form is?

Answer 31

Equal to the number of additional electrons needed to fill it's outer she'll

Question 32

Water is a compound in which the electrons in it's covalent bonds are shared unequally, this has caused water to be what?

Answer 32

Polar molecule

Question 33

Polar molecules have?

Answer 33

One with opposite charges on opposite ends

Question 34

The polarity of water results in weak electrical attraction between neighboring water molecules. This is called what?

Answer 34

Hydrogen Bonds

Question 35

What is the change in chemical composition of matter by breaking existing chemical bonds and forming new ones?

Answer 35

Chemical Reaction

Question 36

What 3 things does chemical reactions include?

Answer 36

Reactants starting Products ending Can rearrange matter but cannot create or destroy it

Question 37

Life on earth began in water when?

Answer 37

3billion years ago

Question 38

Cells are composed of _____ of water

Answer 38

70%-95%

Question 39

What makes earth habitable?

Answer 39

Water

Question 40

The polarity of water molecules and the hydrogen bonding that results in explains water life, supporting properties are?

Answer 40

Water molecules stick together Water has strong resistant to change in temperature Frozen water floats Water is the solvent for life

Question 41

Water molecules stick together as a result of hydrogen bonding called?

Answer 41

Cohesion

Question 42

______ is vital for water transportation in plants?

Answer 42

Cohesion

Question 43

______ is measured of how difficult it is to stretch or break the surface of a liquid

Answer 43

Surface tension

Question 44

What gives water a strong resistance to temperature change?

Answer 44

Hydrogen bonds

Question 45

Heat and Temperature are related but different in what?

Answer 45

In the amount of energy associated with the movement of atoms and molecules in a body of water

Question 46

Temperature measures what?

Answer 46

The intensity of heat

Question 47

What can absorb and store large amounts of heat while only changing a few degrees in temperature?

Answer 47

Water

Question 48

What can moderate temperature?

Answer 48

Water

Question 49

If water molecules get cold enough they move apart and form what?

Answer 49

Ice

Question 50

What has fewer molecules than a equal volume of liquid water?

Answer 50

A chick of ice

Question 51

What floats because of it's less dense that the liquid water around it?

Answer 51

Ice

Question 52

_______ removes heat from earth and it's organisms?

Answer 52

Evaporative cooling

Question 53

A ____ is a liquid consisting if homogeneous mixture of 2 or more substances.

Answer 53

Solution

Question 54

The dissolving agent is the?

Answer 54

Solvent

Question 55

The dissolved subtuse is the?

Answer 55

Solvent

Question 56

When water is the solvent the result is?

Answer 56

An aqueous Solution

Question 57

A chemical compound that releases Hydrogen to a solution is?

Answer 57

Acid

Question 58

A compound that accepts hydrogen and removes it from the solution is?

Answer 58

Abase

Question 59

To describe the acidity of a solution, a chemist uses what?

Answer 59

PH scale

Question 60

Buffers are?

Answer 60

Substances that resist PH change Accepts hydrogen when they are in excess Donates hydrogen ions when they are depleted