exam chapter 3

Question 1

a chemical compound always has the same elements in the same proportions by mass regardless of the source of the compound

Answer 1

law of definite proportions

Question 2

if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers

Answer 2

law of multiple proportions

Question 3

mass is neither created nor destroyed during ordinary chemical reactions of physicla changes

Answer 3

law of conservation of mass

Question 4

proposed the atomic theory

Answer 4

dalton

Question 5

determined that most of the mass of an atom is found in the nucleus

Answer 5

rutherford

Question 6

concluded that electrons were found in all atoms

Answer 6

thompson

Question 7

confirmed the negative charge of the electron

Answer 7

millikan

Question 8

atoms of the same element can differ in

Answer 8

mass number

Question 9

the number of protons in an element is called its

Answer 9

atomic number

Question 10

the isotopes of hydrogen

Answer 10

protium- 0 neutron
deuterium- 1 neutron
tritum- 2 neutrons