LECTURE 3

Question 1

When are molecules formed?

Answer 1

When atoms share or transfer electrons with other atoms

Question 2

Name of the interactions that hold atoms together

Answer 2

Chemical bonds

Question 3

Important chemical bonds

Answer 3

• Covalent
  Hydrogen
  Ionic

Question 4

Covalent bond

Answer 4

Two atoms share a pair of valence electrons

Question 5

What kind of bonds are called 2 pairs of valence elections in covalent bonds?

Answer 5

Double bonds

Question 6

What kind of bonds are 1 pair of electrons in a covalent bond?

Answer 6

Single bond

Question 7

Non polar covalent bond

Answer 7

Elections are shared equally

Question 8

Polar covalent bond

Answer 8

Electrons are not shared equally

Question 9

Hydrogen bond

Answer 9

When a partially positive hydrogen from one molecule is weakly attracted to the partial negative energy of an atom in an other molecule usually (f,o,n)

Question 10

Ions

Answer 10

Atom or molecule that carries a charge

Question 11

Cations

Answer 11

Positively charged molecules that lost an electron

Question 12

Anions

Answer 12

Negatively charged molecules that gained an electron

Question 13

Cations + anions = (what bond?)

Answer 13

Ionic bond

Question 14

Inorganic compounds

Answer 14

Do not contain carbon water, salt and many acid and bases

Question 15

Organic compounds

Answer 15

Contain carbon (carbohydrates, fats, proteins, and nucleic acid)

Question 16

Volume of a cell

Answer 16

60 - 80 % of water

Question 17

Why is water the most important inorganic compound for living organisms?

Answer 17

• High heat capacity
• high heat of vaporization
• polar solvent
• highly reactive
• used to cushion tissue

Question 18

Why does water help moderate climate?

Answer 18

Because of its high heat capacity

Question 19

Basis of evaporative cooling

Answer 19

Heat must be absorbed from the environment in contact with the water

Question 20

polar molecules

Answer 20

• hydrophilic
• substances that are ionic/polar often dissolve in water because of hydrogen bonds

Question 21

nonpolar molecule

Answer 21

• hydrophobic
• tend to aggregate with other nonpolar molecules

Question 22

properties of water: reactivity

Answer 22

• necessary part of hydrolysis and dehydration synthesis reactions

Question 23

properties of water: cushioning

Answer 23

• protects certain organs from physical trauma (ex: cerebrospinal fluid)

Question 24

why does ice float?

Answer 24

because water is less dense when solid

Question 25

properties of water: cohesion

Answer 25

• water molecules resist coming apart from one another
• that results in surface tension
• helps water move through plants

Question 26

carbons atoms form…?

Answer 26

• 4 stable bonds
• highly versatile atom

Question 27

carbon’s versitality advantage

Answer 27

infinite number of molecules to be formed

Question 28

functional groups (def)

Answer 28

• covalently linked carbon atoms for a skeleton (differs)
• have distinct chemic properties

Question 29

functional groups (example)

Answer 29

• amino
• carbonyl
• carboxyl
• hydroxyl
• phosphate
• sulfhydryl

Question 30

macromolecules (definition)

Answer 30

• four kinds are present in all living things
• most are polymers made of smaller monomers

Question 31

four kinds of macromolecules

Answer 31

• proteins
• carbohydrates
• lipids
• nucleic acids

Question 32

condensation

Answer 32

• monomers polymerize to form polymers
• called like this because it produces a water molecule

Question 33

hydrolysis

Answer 33

• polymers disintegrate to form monomers
• called like this because a water molecule is used in the process