Biology 1 Vocab From Chapter 2 Of Concepts & Connections

Front 1

matter

Back 1

anything that occupies space and has mass

Front 2

element

Back 2

a substance that cannot be broken down to other substances by ordinary chemical means

Front 3

compound

Back 3

a substance containing two or more elements in a fixed ratio

Front 4

atom

Back 4

named form a Greek word meaning "indivisible," is the smallest unit of matter that still retains the properties of an element.

Front 5

proton

Back 5

a subatomic particle with a single positive electrical charge

Front 6

electron

Back 6

a subatomic particle with a single negative electrical charge

Front 7

neutron

Back 7

subatomic particle with no charge

Front 8

nucleus

Back 8

a atom's central core

Front 9

atomic number

Back 9

the number of protons in the nucleus

Front 10

mass number

Back 10

the sum of protons and neutrons in the nucleus

Front 11

isotopes

Back 11

elements that have the same number of protons but different amounts of neutrons

Front 12

radioactive isotope

Back 12

when the nucleus decays spontaneously, giving off particles and energy

Front 13

chemical bonds

Back 13

interactions usually result in atoms staying close together

Front 14

ion

Back 14

an atom or molecule with an electrical charge resulting from a gain or loss of one or more electrons

Front 15

ionic bond

Back 15

two ions with opposite charges attract each other; when the attraction holds them together, its called an ionic bond

Front 16

electronegativity

Back 16

an atom's attraction for its electrons, including shared electrons

Front 17

nonpolar

Back 17

covalent bonds because the electrons are shared equally between the atoms.

Front 18

polar covalent bond

Back 18

unequal sharing of electrons

Front 19

polar molecule

Back 19

unequal distribution of charges

Front 20

cohesion

Back 20

the tendency of molecules to stick together

Front 21

surface tension

Back 21

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

Front 22

heat

Back 22

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

Front 23

temperature

Back 23

measures the intensity of heat

Front 24

solution

Back 24

a liquid consisting of a uniform mixture of two or more substances

Front 25

solvent

Back 25

the dissolving agent

Front 26

solute

Back 26

substance that is dissolved

Front 27

aqueous solution

Back 27

when water is the solvent

Front 28

acid

Back 28

a compound that donates hydrogen ions to solutions

Front 29

base

Back 29

a compound that accepts hydrogen ions and removes them from solution

Front 30

pH scale

Back 30

used to describe how acidic or basic a solution is

Front 31

buffers

Back 31

substances that resist changes in pH by accepting H+ and donating H+ when it is depleted

Front 32

acid precipitation

Back 32

defined as rain, snow or fog with a pH lower than 5.6 the pH of uncontaminated rain

Front 33

chemical reaction

Back 33

a process leading to changes in the composition of matter