chemical organization

Question 1

matter

Answer 1

anything that takes up space and has mass

Question 2

4 properties of an atom

Answer 2

• the smallest stable unit of matter
• composed of subatomic particles
• electrically neutral
• equal number of protons and electrons

Question 3

charge of protons

Answer 3

positively charged

Question 4

charge of neutrons

Answer 4

neutral

Question 5

charge of electrons

Answer 5

negatively charged

Question 6

what subatomic particles are found in the nucleus of the atom?

Answer 6

protons and neutrons

Question 7

what subatomic particle is found in the orbit around the nucleus?

Answer 7

electrons

Question 8

atomic number

Answer 8

the number of protons in an atom

Question 9

electron cloud

Answer 9

the area around the nucleus that contains electrons

Question 10

electron shell

Answer 10

two-dimensional representation of an
electron cloud

Question 11

element

Answer 11

a pure substance composed of atoms of one
kind, which can not be broken down into simpler
substances by physical means

Question 12

isotopes

Answer 12

elements that have different numbers of neutrons

Question 13

mass number

Answer 13

the number of protons plus the number of
neutrons of an atom

Question 14

radioisotopes

Answer 14

isotopes that have unstable or radioactive nuclei

Question 15

radioactive decay

Answer 15

the breakdown of the nucleus

Question 16

half-life

Answer 16

the time required for half of a given amount of isotope to delay

Question 17

atomic weight

Answer 17

an average of the different atomic masses and proportions of different isotopes

Question 18

atomic mass

Answer 18

the actual mass of an atom, taking into account
the masses of its protons, neutrons, and electrons

Question 19

capacity of electron shells

Answer 19

• first shell: 2 electrons
• second shell: 8 electrons
• third shell: 18 electrons

Question 20

valence shell

Answer 20

outermost electron shell that determines chemical properties of an element

Question 21

ionic bonds

Answer 21

bonds created between negative and positive ions

Question 22

ion

Answer 22

atom with an electric charge

Question 23

cation

Answer 23

positively charged ion

Question 24

anion

Answer 24

negatively charged ion

Question 25

covalent bonds

Answer 25

created when atoms share electrons

Question 26

5 types of covalent bonds

Answer 26

- single: shares one pair of electrons - double: shares two pairs of electrons - triple: shares three pairs of electrons - nonpolar: equal sharing of electrons - polar: uneqal sharing of electrons

Question 27

hydrogen bonds

Answer 27

bond between a hydrogen atom and an atom of oxygen, nitrogen, or fluorine *responsible for the high surface tension of water*

Question 28

states of matter

Answer 28

- solid: constant volume and shape - liquid: constant volume, not shape - gas: no constant volume or shape

Question 29

reactants

Answer 29

the reacting substances that enter the reaction

Question 30

products

Answer 30

the resulting substances at the end of the reaction

Question 31

kinetic energy

Answer 31

the energy of motion

Question 31

metabolism

Answer 31

chemical reactions that occur in the cells and tissues of the body

Question 32

potential energy

Answer 32

stored energy an object possesses

Question 33

properties of energy

Answer 33

- energy can not be destroyed, only converted - when energy is converted, some is released as heat

Question 34

decomposition reactions

Answer 34

break molecules into smaller fragments, catabolism (release energy to be used for cellular processes) ex. AB > A + B

Question 35

hydrolysis reactions

Answer 35

decomposition reactions which involve water ex. AB + H2O > AH + BOH

Question 36

synthesis reactions

Answer 36

form large molecules from small molecules, anabolism (use energy to create bonds) ex. A + B > AB

Question 37

dehydration synthesis (condensation) reactions

Answer 37

synthesis reactions that result in the production of a molecule of water ex. AH + BOH > AB + H2O

Question 38

exchange reactions

Answer 38

rearrange existing components of molecules into new products ex. AB + CD > AD + CB