LO 2

Question 1

Chemicals are in the form of ______ which are composed of ________

Answer 1

Molecules, atoms

Question 2

Regions surrounding the atoms nucleus and contain electrons are called _________

Answer 2

Energy levels (orbitals)

Question 3

What determines the atomic number of an element?

Answer 3

The number of protons

Question 4

What determines the atomic mass of an element?

Answer 4

Number of protons and neutrons

Question 5

How many electrons may be contained in each orbital?

Answer 5

2 in the first, 8 in all following

Question 6

Energy of electrons increases with ________

Answer 6

Distance from the nucleus

Question 7

Define element

Answer 7

A pure substance made of only one kind of atom

Question 8

Define molecule

Answer 8

A group of atoms bound together to form a larger chemical unit - e.g. H2O

Question 9

Define compound

Answer 9

Substances whose molecules have more than one kind of atom

Question 10

Living organisms require about ____ elements

Answer 10

20

Question 11

Which 4 elements are most abundant in the human body?

Answer 11

Oxygen, carbon, hydrogen, and nitrogen - about 96% of body weight

Question 12

Ionic bonds form between atoms that have ____ electrons in their outer shell and atoms that have _____ electrons in their outer shell

Answer 12

1 or 2; 6 or 7

Question 13

Define ion

Answer 13

Atom or group of atoms with a positive or negative electric charge

Question 14

Ionic bonds form when _____ attracts each other

Answer 14

A positive and negative ion (donation of electrons leave them with similar opposite charges)

Question 15

Define electrolyte

Answer 15

Ionic molecules usually dissolved in water and dissociate to form free ions

Question 16

Do covalent bonds dissociate in water?

Answer 16

No, because they share electrons they are closer together

Question 17

Define hydrogen bond

Answer 17

A relatively weak electrostatic force of attraction between hydrogen atom and a more electronegative doner atom or group

Question 18

Define organic compounds

Answer 18

Contain carbon-carbon covalent bonds and/or carbon-hydrogen covalent bonds

Question 19

Define inorganic compounds

Answer 19

Do not contain the carbon-carbon or carbon-hydrogen bonds found in organic compounds

Question 20

The most abundant solvent is ______

Answer 20

Water

Question 21

Define solvent

Answer 21

A liquid into which solutes are dissolved, that forms an aqueous solution

Question 22

Define dehydration synthesis

Answer 22

Water is removed from small molecules so they can be strung together to form a larger molecule (e.g. formation of bio molecules from monomers)

Question 23

Define hydrolysis

Answer 23

Water is added to the subunits of a large molecule to break it into smaller molecules (e.g. bio molecules breaking down into monomers)

Question 24

_______ is either stored or released in every chemical reaction

Answer 24

Energy

Question 25

Define acid

Answer 25

Substances that shifts the H+/OH- balance in favour of H+

Question 26

Define base

Answer 26

Substances that shifts the H+/OH- balance against H+

Question 27

What numbers are neutral, basic, and acidic on the pH scale?

Answer 27

1. 7 is neutral
2. > 7 are basic
3. < 7 are acidic

Question 28

What is neutralization?

Answer 28

When strong acids and strong bases mix and form salts and water

Question 29

What are buffers?

Answer 29

Chemical systems that absorb excess acids or bases and thus maintain a relatively stable pH (homeostasis)

Question 30

What are “strong” acids?

Answer 30

Acids that completely dissociate in water

Question 31

Should you add acid to water or water to acid?

Answer 31

Acid to water

Question 32

What are the 4 major groups of organic compounds in the human body (biomolecules)?

Answer 32

1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic acids

Question 33

What are the 3 types of carbohydrates with examples?

Answer 33

1. Monosaccharides - glucose, fructose, ribose
2. Disaccharides - sucrose, maltose, lactose
3. Polysaccharides - glycogen

Question 34

What is the function of carbohydrates in the body?

Answer 34

Provide energy - energy is stored in their bonds and released when broken

Question 35

What are the 3 types of lipids?

Answer 35

1. Triglycerides
2. Phospholipids
3. Steroids (cholesterol

Question 36

Triglycerides are made of 3 fatty acids attached to ________

Answer 36

1 glycerol unit

Question 37

What are phospholipids made of?

Answer 37

1 glycerol, 2 fatty acids, 1 phosphorous-containing group

(Hydrophilic head, hydrophobic tails)

Question 38

Cholesterol is converted into ______ in humans

Answer 38

Steroid hormones (estrogen, testosterone, and cortisone)

Question 39

What is cholesterol’s structure and how does it impact cell membranes?

Answer 39

1. Core of 20 carbons in 4 fused rings
2. Stabilizes phospholipid tails in cellular membranes

Question 40

What are proteins?

Answer 40

Large molecules made of amino acids held together in long, folded chains by peptide bonds

Question 41

Proteins can be divided into ______

Answer 41

Structural and functional

Question 42

Define structural proteins with examples

Answer 42

Form structure of the body (e.g. collagen and karatin)

Question 43

Define functional proteins with examples

Answer 43

Participate in the body’s chemical reactions/processes (e.g. hormones, cell membrane channels and receptors, enzymes)

Question 44

Describe enzymes

Answer 44

Chemical catalysts using lock and key model to act on specific molecules - no processes in the body could happen fast enough without them

Question 45

What could cause an enzyme to denature?

Answer 45

Drastic changes in pH or temperature

Question 46

What are RNA and DNA made of?

Answer 46

Sugar, phosphate, nitrogen bases

Question 47

What is the sugar in DNA?

Answer 47

Deoxyribose

Question 48

What does RNA do?

Answer 48

Used as a temporary “working copy” of a gene