Regents Review

Question 1

Substance

Answer 1

element or compound

Question 2

polar bond

Answer 2

between two DIFFERENT non-metals with DIFFERENT electronegativities

Question 3

non-polar bond

Answer 3

between the same non-metal atoms, with the same electronegativities

Question 4

average kinetic energy

Answer 4

temperature

Question 5

delta H (heat of reaction)

Answer 5

the difference between the potential energy of the reactants and the potential energy of the products

Question 6

heat of fusion

Answer 6

heat required to melt (or lost when freezing) a substance AT ITS MELTING POINT

Question 7

heat of vaporization

Answer 7

heat required to vaporize (boil) a substance at its boiling point

Question 8

exothermic

Answer 8

releases heat, heat is on right side of reaction

Question 9

endothermic

Answer 9

absorbs heat, heat is on the left side of a reaction

Question 10

hydronium ion

Answer 10

H3O+ found in acids

Question 11

hydroxide

Answer 11

OH- found in bases

Question 12

Arrhenius acid

Answer 12

releases H+

Question 13

Arrhenius base

Answer 13

releases OH-

Question 14

atomic number

Answer 14

number of protons; defines an element; cannot change without changing the element

Question 15

atomic mass

Answer 15

number of protons and neutrons

Question 16

isotope

Answer 16

elements with a different number of neutrons and therefore a different atomic mass

Question 17

alternate acid-base theory

Answer 17

acids are H+ donors, bases are H+ acceptors

Question 18

electrolyte

Answer 18

a substance which conducts electricity in aqueous solution; acids, bases or salts (ionic compounds)

Question 19

ion

Answer 19

a charged “atom” caused by the loss or gain of electrons ;

Question 20

positive ion

Answer 20

usually metals which have lost electrons

Question 21

negative ion

Answer 21

usually non-metals which have gained electrons

Question 22

orbital

Answer 22

a region of high probability of finding an electron in the “wave-mechanical” or electron cloud model of the atom

Question 23

electronegativity

Answer 23

ability of a atom to attract electrons in a chemical bond

Question 24

ionization energy

Answer 24

amount of energy required to remove an electron from a gaseous atom

Question 25

metal

Answer 25

found to the left of the "staircase", malleable, ductile, good conductors

Question 26

non-metal

Answer 26

found to the right of the staircase, brittle, poor conductors

Question 27

chemical properties

Answer 27

create new substances

Question 28

physical properties

Answer 28

phase changes or other properties which do not create new substances

Question 29

ionic bond

Answer 29

metal and a non-metal; transfer of electrons from metal (+) to non-metal (-)

Question 30

covalent bond

Answer 30

electrons are shared between two non-metals

Question 31

molecular

Answer 31

means "covalently bonded"

Question 32

metallic bond

Answer 32

mobile electrons found in a sample of a pure metal

Question 33

non-polar molecule

Answer 33

SYMMETRICAL charge distribution | ex: CO2, CH4, CF4, H2, O2, N2 etc

Question 34

polar molecule

Answer 34

ASYMMETRICAL charge distribution | ex: HCl, NH3, H2O,

Question 35

voltaic cell

Answer 35

produces electrical energy from chemical energy, spontaneous!

Question 36

electrolytic cell

Answer 36

uses electricity to cause a redox reaction, NOT spontaneous

Question 37

anode

Answer 37

oxidation occurs here | AN OX

Question 38

cathode

Answer 38

reduction occurs here | RED CAT

Question 39

reduction

Answer 39

gain of electrons, causes oxidation state to DECREASE ( ex: +4 to +2)

Question 40

oxidation

Answer 40

loss of electrons, causes oxidation state to INCREASE (ex: 0 to +3)

Question 41

fission

Answer 41

splitting apart of large nuclei ( U-235)

Question 42

fusion

Answer 42

joining of small nuclei (H-3, H-2)

Question 43

equilibrium

Answer 43

EQUAL rates of forward and reverse reactions; CONSTANT concentrations of reactions and products

Question 44

entropy

Answer 44

randomness, disorder; increases s to l to g

Question 45

transmutation

Answer 45

the conversion of the nucleus of one element to the nucleus of another element

Question 46

negligible

Answer 46

almost none

Question 47

emit

Answer 47

release

Question 48

binary

Answer 48

composed of two elements

Question 49

empirical

Answer 49

simplest ratio

Question 50

"like dissolves like:

Answer 50

substance dissolve when their molecular polarities are the same (polar or non-polar)