atoms vocab

Question 1

atomic theory

Answer 1

all matter is made up of indivisible particles called atoms

Question 2

negatively charged particles orbiting the nucleus

Answer 2

electrons

Question 3

particles with no charge in the nucleus - neutral

Answer 3

neutrons

Question 4

tells you how many protons are in an atom of the element

Answer 4

atomic number

Question 5

amount of particles equal to 1 mole

Answer 5

avagadros number

Question 6

electrons in the outermost level of an atom

Answer 6

valence electrons

Question 7

Greek philosopher who suggested the universe is made of indivisible units called atoms

Answer 7

democritus

Question 8

British scientist proposed that most of the mass of the
atom was concentrated in the atom’s center - discovered nucleus;

Answer 8

rutherford

Question 9

a chemical
compound always contains the same
elements in exactly the same proportions by
weight or mass

Answer 9

law of definite proportions

Question 10

positively charged dense core located in center of atom

Answer 10

nucleus

Question 11

a charged particle

Answer 11

ion

Question 12

area where electrons can be found in the atom

Answer 12

energy level

Question 13

lowest state of energy of an atom

Answer 13

ground state

Question 14

revised the Atomic Theory in 1808; based his theory
on experimental evidence; considered to be the foundations for the modern atomic theory.

Answer 14

dalton

Question 15

danish physicist; suggested that the energy of each electron
was related to the path it follows around the
nucleus.

Answer 15

bohr

Question 16

smallest part of a substance that cant be broken down chemically

Answer 16

atom

Question 17

positively charged particle in nucleus

Answer 17

proton

Question 18

equals total # of subatomic particles in nucleus

Answer 18

mass #

Question 19

unit used to count particles

Answer 19

mole

Question 20

a particle of light

Answer 20

photon

Question 21

electrons move to this when it gains energy

Answer 21

excited state

Question 22

British scientist who suggested atoms were not indivisible; discovered electrons

Answer 22

thomson

Question 23

elements that vary in mass #’s bc their # of neutrons differ

Answer 23

isotope

Question 24

what are the three characteristics of atoms

Answer 24

1. each element has a unique # of protons
2. neutral atoms have no overall charge
3. positive+negative charges attract each other inside the atom

Question 25

what did Bohr contribute to atomic theory

Answer 25

he said that energy of each electron was related to the path it follows around the nucleus (said electrons behave more like waves)

Question 26

most likely place to find an electron

Answer 26

orbital or levels

Question 27

what places are electrons never found

Answer 27

nucleus and in between levels

Question 28

how to identify an isotope

Answer 28

if mass # in periodic table doesn't = mass # given (calculated)

Question 29

how to identify an ion

Answer 29

protons don't = electrons

Question 30

how to identify a neutral atom

Answer 30

mass # in periodic table = mass # given/calculated AND protons = electrons