Ch 3 Review

Question 1

The subatomic particle with a negative charge.

Answer 1

electrons

Question 2

The electrons were first discovered while studying a ________

Answer 2

cathode ray

Question 3

The number s of atoms or particles in one mole of a substance.

Answer 3

Avogadros number

Question 4

The subatomic particle found in the nucleus with no charge.

Answer 4

neutrons

Question 5

The number of protons in an atom is equal to the ______

Answer 5

atomic number

Question 6

The mass in grams of 1 mole of a substance.

Answer 6

molar mass

Question 7

the particles that make up an atom are called

Answer 7

subatomic particles

Question 8

the small dense center of an atom that contains most of the atom’s mass, but very little of the atom’s volume

Answer 8

atomic number

Question 9

the unit used when talking about the mass of an atom

Answer 9

nucleus

Question 10

the model of the atom suggested by JJ Thompson that consists of a positive mass with negative charges

Answer 10

plum pudding model

Question 11

the law of _____ states that in a chemical reaction, mass cannot be created or destroyed. this means the mass of the products is equal to the mass of the reactants

Answer 11

conservation of mass

Question 12

the charge of an electron

Answer 12

negative

Question 13

the law of ____ states that if two or more compounds are made up of the same two elements the ratio of the masses of the second element is always a ratio of small whole numbers

Answer 13

multiple proportions

Question 14

a region in an atom where there is a high probability of finding an electron.

Answer 14

orbital

Question 15

dalton’s ___ consist of 5 parts talking baout properties of atoms

Answer 15

atomic theory

Question 16

the law of ____ states that a chemical compound always contains the same elements in exactly the same proportions by weight or mass

Answer 16

definite proportions

Question 17

the number of protons and neutrons

Answer 17

mass number

Question 18

the mass of an atom expressed in atomic mass units

Answer 18

atomic mass

Question 19

the scientist credited with the discovering the nucleus of an atom with his gold foil experiment

Answer 19

rutherford

Question 20

the man who is credied with discovering the electrons

Answer 20

JJ thompson

Question 21

the difference in energy between two wnergy levels

Answer 21

quantum

Question 22

when an electron is in the lowest energy level possible, it is in a

Answer 22

ground state

Question 23

the force that holds the nucleus of an atom together

Answer 23

strong force

Question 24

the subatomic particle found in the nucleus with a positive charge

Answer 24

proton

Question 25

the arrangement of electrons in an atom

Answer 25

electron configuration

Question 26

the SI unit used to measure the amount of a substance. it is equal to 6.022*10^23

Answer 26

mole

Question 27

atoms of the same element with different numbers of neutrons

Answer 27

isotopes

Question 28

the atomic mass unit is defined as one-twelfth of the mass of one ___ atom

Answer 28

carbon-12

Question 29

when an electron gains energy and moves to a higher energy level, it is in an __

Answer 29

excited state

Question 30

rutherford concluded the atom is mostly ____ space

Answer 30

empty

Question 31

the charge on a proton

Answer 31

positive

Question 32

___model of the atom has electrons orbiting the nucleus at certain distances corresponding to certain amounts of energy

Answer 32

bohr model