Science Ch.4

Question 1

atom

Answer 1

the smallest unit of an element that maintains the properties of that element

Question 2

electron

Answer 2

a subatomic particle that has a negative charge

Question 3

nucleus

Answer 3

in physical an atoms central region which is mad up of protons and neutrons

Question 4

electron cloud

Answer 4

a region around the nucleus of an atom where electrons are most likely to be found

Question 5

proton

Answer 5

a subatomic particle that that has a positive charge and that is found in the nucleus of an atom

Question 6

atomic mass unit

Answer 6

a unit of mass that describes the mass of an atom or molecule

Question 7

neutron

Answer 7

a subatomic particle that has no charge and its found in the nucleus of an atom

Question 8

atomic number

Answer 8

the number of protons in the nucleus of an atom

Question 9

isotope

Answer 9

an atom that has the same number of protons

Question 10

mass number

Answer 10

the sum of the numbers of protons and neutrons in the nucleus of an atom

Question 11

atomic mass

Answer 11

the mass of at atom expressed in atomic mass units

Question 12

Dalton

Answer 12

fund that all elements combine to form compounds

Question 13

Thomsons

Answer 13

founder of electrons

Question 14

Rutherford

Answer 14

corrected Dalton’s theory with the gold foil experitment

Question 15

Bohr

Answer 15

discovered electron levels