Chapter 4 Vocab

Question 0

the idea that an element is composed of only one kind of atom, and a compound is composed of particles that are chemical combinations of different kinds of atoms

Answer 0

Dalton’s atomic theory

Question 1

the smallest part of an element that retains its identity in a chemical reaction

Answer 1

atom

Question 2

negatively charged subatomic particles

Answer 2

electrons

Question 3

a glowing beam that traveled from the cathode to the anode (the negatively charged end to the positively charged end)

Answer 3

cathode ray

Question 4

positively charged subatomic particles

Answer 4

proton

Question 5

subatomic particles with no charge but with a mass nearly equal to that of a proton

Answer 5

neutron

Question 6

the tiny central core of an atom that is composed of protons and neutrons

Answer 6

nucleus

Question 7

the total number of protons and neutrons in an atom

Answer 7

mass number

Question 8

the number of protons in the nucleus of an atom of that element

Answer 8

atomic number

Question 9

atoms that have the same number of protons but different numbers of neutrons

Answer 9

isotopes

Question 10

a unit defined as 1/12 of the mass of a carbon-12 atom

Answer 10

atomic mass unit (amu)

Question 11

a weighted average mass of the atoms in a naturally occurring sample of the element

Answer 11

atomic mass

Question 12

an arrangement of elements in which the elements are separated into groups based on a set of repeating properties

Answer 12

periodic table

Question 13

each horizontal row of the periodic table

Answer 13

period

Question 14

each vertical column of the periodic table

Answer 14

group