Chapter 9

Question 1

Radioactivity

Answer 1

process by which some atoms emit energy and particles

Question 2

Isotope

Answer 2

Same number of protons but different mass numbers

different number of neutrons

Question 3

Nuclide

Answer 3

any atom characterized by an atomic number and a mass number

Question 4

Alpha Particle

Answer 4

slow moving, 2 protons 2 neutrons (He),

Question 5

Beta Particle

Answer 5

B symbol, fast-moving (90% speed of light). Involves a neutron converting to a proton. No mass

Question 6

Gamma Rays

Answer 6

Y symbol, most energetic part, not considered matter

Question 7

Positron

Answer 7

Proton converts to neutron, Beta Particle

Question 8

Ionizing radiation

Answer 8

collective name for alpha, beta, gamma radiation. leaves a trail of ions throughout the material it penetrates

Question 9

Nuclear Equation

Answer 9

can be used to represent the process of radioactive decay a nuclide breaks down, producing a new nuclide, smaller particles , and/or energy

Question 10

m represents?

Answer 10

metastable isotope, meaning that it is unstable and increases its stability through gamma decay without change to mass or charge of the isotope

Question 11

Binding energy

Answer 11

measure of nuclear stability of the nucleus

Question 12

Half-life

Answer 12

is the time required for one-half of a given quantity of a substance to undergo change

Question 13

Radiocarbon dating

Answer 13

estimation of the age of objects through measurement of isotopic ratios of carbon

Question 14

Nuclear reactor

Answer 14

heat energy converted to liquid water into steam, which produces electricity

Question 15

Fission

Answer 15

occurs when a heavy nuclear particle is split into smaller nuclei by a smaller nuclear particle

Question 16

Chain reaction

Answer 16

when neutrons create a chain reaction

Question 17

Fusion

Answer 17

(meaning to join together) results from the combination fo two small nuclei to form a larger nucleus with the concurrent release of large amounts of energy

Question 18

Breeder reactor

Answer 18

variation of a fission reactor that literally manufactures its own fuel

Question 19

Nuclear medicine

Answer 19

use of radiation in the treatment of various forms of cancer, as well as diagnosing diseases/cancers/etc..

Question 20

Nuclear imaging

Answer 20

medical techniques involving tracers

Question 21

Tracers

Answer 21

small amounts of radioactive substances used as probes to study internal organs

Question 22

Natural radioactivity

Answer 22

naturally occurring

Question 23

ficial radioactivity

Answer 23

non-radioactive nucleus is made radioactive

Question 24

Background Radiation

Answer 24

level of radiation attributable to our surroundings on a day-to-day basis

Question 25

Shielding

Answer 25

a way to protect from harmful radiation

Question 26

Curie

Answer 26

measure of the amount of radioactivity in a radioactive source

Question 27

roentgen

Answer 27

measure of very high energy ionizing radiation (x-ray & gamma) only

Question 28

Rad

Answer 28

radiation absorbed dosage, provides more meaningful information than either of the previous units of measure

Question 29

Rem

Answer 29

describes the biological damage caused by the absorption of different kinds of radiation of the human body

Question 30

Lethal dose (LD50)

Answer 30

is defined as the acute dosage of radiation that would be fatal for 50% of the exposed population within 30 days.

Question 31

Stability of an isotope

Answer 31

• Ratio of neutrons to protons
  – Nuclei with large number of protons (84 or more) tend to be unstable
  – The “magic numbers” of 2, 8, 20, 50, 82, or 126 help
  determine stability these numbers of protons or neutrons are stable
  – Even numbers of protons or neutrons are generally
  more stable than those with odd numbers
  – All isotopes (except 1 H) with more protons than neutrons are unstable