Chapter 2: Chemistry

Question 1

Biochemistry

Answer 1

Chemistry of living material (matter)

Question 2

Matter

Answer 2

Anything that occupies space and has mass; can be seen, smelled and felt

Question 3

States of Matter

Answer 3

exists in solid, liquid and gaseous states

Question 4

Energy

Answer 4

Capacity to do work

Question 5

2 forms of energy

Answer 5

Kinetic and Potential; each can be transformed to the other

Question 6

Kinetic energy

Answer 6

Energy in action; motion/movement; ex. riding a bike

Question 7

Potential energy

Answer 7

Stored energy; has the potential or capability to do work but is not currently doing so

Question 8

4 forms of Energy

Answer 8

1) chemical, 2) electrical, 3) mechanical, 4) radiant or electromagnetic

Question 9

Chemical energy

Answer 9

potential energy stored in bonds; released in reactions

Question 10

ATP

Answer 10

Adenosine triphospate; molecule temporarily capturing food energy in its bonds

Question 11

Electrical energy

Answer 11

results from movement of charged particles (nerve impulses in body)

Question 12

Mechanical energy

Answer 12

Energy directly involved in moving matter; (legs provide energy to move a bicycle)

Question 13

Radiant/electromagnetic energy

Answer 13

energy traveling in waves (electromagnetic spectrum)

Question 14

Elements

Answer 14

Elementary substances that cannot be broken down further (ex. oxygen, carbon, gold, silver, copper, iron); 118 elements recognized; 92 of these occur in nature

Question 15

4 elements that make up 96% of body weight

Answer 15

carbon, oxygen, hydrogen, nitrogen

Question 16

Atom

Answer 16

Smallest unit maintaining properties of an element; electrically neutral (protons = electrons *must neutralize)

Question 17

Atomic symbol

Answer 17

abbreviation for an element; 1st letter English or Latin (H, C, Na)

Question 18

Nucleus

Answer 18

contains protons and neutrons; p are +, n are neutral, = positive charge overall

Question 19

Shell

Answer 19

energy levels (made up of orbitals) regions where electrons are found

Question 20

Electrons

Answer 20

bear a negative charge equal in strength to the positive charge of the proton

Question 21

Atoms differ

Answer 21

differ by the # of protons (and electrons) and neutrons; determines which element

Question 22

Atom stability

Answer 22

outer shell filled to capacity; chemically inert (doing nothing)

Question 23

Valence shell

Answer 23

part of the outermost energy level with chemically reactive electrons

Question 24

Identifying elements

Answer 24

atomic number, mass number, atomic weight; all provide information about each element

Question 25

Atomic #

Answer 25

equal to the # of protons in its nucleus and is written as a subscript to the left of its atomic symbol

Question 26

Mass #

Answer 26

the sum of the masses of an atoms protons and neutrons

Question 27

Atomic weight

Answer 27

average of all weights, accounting or abundance (located directly below symbol on periodic table)

Question 28

Octet Rule

Answer 28

atoms interact; they have electrons in the valence shell (rule of eights: 2-8-8)

Question 29

Isotopes

Answer 29

Have the same # of protons (and electrons) but differ in the # of neutrons they contain. Ex. 12C, 13C, 14C;

Question 30

Atomic mass

Answer 30

protons + # neutrons

Question 31

radioisotopes

Answer 31

heavier isotopes; unstable; decompose giving off alpha, beta, or gamma rays

Question 32

Free radicals

Answer 32

lead to cancer and disease

Question 33

Molecule

Answer 33

2 or more atoms held by chemical bonds

Question 34

Molecule of element

Answer 34

When two or more atoms of the same element combine (O2, S8, H2)

Question 35

Molecule of compound

Answer 35

When two or more different kinds of atoms bind (H2O)

Question 36

Molecular weight

Answer 36

Sum of atomic weight; In grams = 1 mole + H2) to make 1 liter

Question 37

Avogadro’s #

Answer 37

every mole always has 6.02 X 10^23 solute particles

Question 38

Mixtures

Answer 38

2 or more components physically mixed, can seperate, no chemical bonding

Question 39

3 types of mixtures

Answer 39

1) Solutions, 2) Colloids, 3) suspensions

Question 40

Solutions

Answer 40

homogeneous mixtures that may be gases, liquids or solids; transparent Ex. Air, H2O

Question 41

Homogeneous

Answer 41

mixture is exactly the same composition or makeup throughout

Question 42

Colloids

Answer 42

also called emulsions. Heterogeneous mixtures (composition is dissimilar); translucent or milky; do scatter light; some can undergo sol-gel transformations. Ex. Jello, cytosol

Question 43

Suspensions

Answer 43

heterogeneous mixtures with large, often visible solutes that tend to settle out; ex: blood

Question 44

3 types of chemical bonds

Answer 44

1) ionic, 2) covalent, 3) hydrogen

Question 45

Ionic bond

Answer 45

bond formed by transfer of e-

Question 46

electron acceptor

Answer 46

the atom that gains one or more electrons; acquires a net negative charge and is called an ANION

Question 47

electron donor

Answer 47

the atom that loses electrons; acquires a net positive charge and is called a CATION

Question 48

covalent bond

Answer 48

shares e-. e- occupy a single orbital common to both atoms. Ex. Methane

Question 49

nonpolar

Answer 49

shares e- equally

Question 50

polar

Answer 50

shares e- unequally

Question 51

electronegativity

Answer 51

small atoms with 6 or 7 valence shell e- attract e- strongly. ex. O2, N2, Cl

Question 52

electropositive

Answer 52

1 or 2 valence shell electrons; low attraction. Lose e-. Ex K+ and Na are good ex

Question 53

Hydrogen bond

Answer 53

more like attractions than true bonds; slightly positive ends of the water molecules become aligned with the slightly negative ends of other water molecules.