Ch. 5 Inside the Atom

Question 1

element

Answer 1

a substance that cannot be broken down into simpler substances

Question 2

alpha particle

Answer 2

item consisting of two protons and two neutrons

Question 3

electron cloud

Answer 3

region surrounding the nucleus in which the electrons move about

Question 4

transmutation

Answer 4

the changing of one element into another element through radioactive decay

Question 5

proton

Answer 5

a positively charged particle that is present in all atoms

Question 6

atomic number

Answer 6

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

Question 7

mass number

Answer 7

the number of neutrons plus protons in the nucleus of an atom

Question 8

radioactive decay

Answer 8

the release of nuclear particles and energy

Question 9

electron

Answer 9

a negatively charged particle of matter

Question 10

beta particle

Answer 10

a high-energy electron that comes from the nucleus, not from the electron cloud

Question 11

half-life

Answer 11

the amount of time required for half a sample of a radioactive isotope to decay

Question 12

isotopes

Answer 12

atoms of the same element that have different numbers of neutrons

Question 13

neutron

Answer 13

uncharged particle in the nucleus of an atom