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Flashcards in 4.1 Deck (23):
1

Which elements on the periodic table have stable nuclei?

elements up to 19

2

What makes a stable nuclei stable?

forces of attraction and repulsion are balanced

3

Hoe does a unstable nucleus become more stable?

emit radiation

4

What is radiation?

particles of energy from unstable nuclei

5

radioisotopes

isotopes that emit radiation

6

transmutation

change in number of protons in nucleus

7

which elements are artificial?

elements 93+

8

what happens when an atom is emitting radiation? (nucleus energy level)

unstable nuclei becomes stable by forming a lower energy nucleus

9

Types of radiation

alpha, beta, positron, gamma

10

alpha particle
particles, mass#, atomic #, charge

identical to helium, 2 protons, 2 neutrons, mass #4, atomic # 2, charge 2+

11

beta particle
mass#, charge

high energy electron, mass#0, charge 1-,

12

positron
charge, mass#

charge 1+, mass 0

13

gamma ray
mass#, atomic #

mass# 0,
atomic # 0

14

what may happen to an electron when radiation strikes it? what is formed?
what is this process called?

electrons may be knocked away,
forming unstable ions
ionization radiation

15

what happens when ionizing radiation passes the human body?
what is formed?
why is it dangerous?

it may interact with water molecules removing electrons forming H20+
H20+ can cause undesirable chemical reactions

16

which cells are most sensitive to ionization radiation?

cells that undergo rapid division
(bone marrow, skin, reproductive organs, cells of growing children, cancer)

17

Protection from radiation: Alpha particles

paper, clothing, skin

18

Protection from radiation: Beta particles

heavy clothes
eg. lab coat, gloves

19

Protection from radiation: gamma ray

lead shield, thick concrete walls

20

how can you protect yourself from radiation?

limit your time with it (less exposure)
greater distance (lower intensity)

21

most common source of alpha particle

radium 226

22

most common source of beta particles

carbon 14

23

most common source of gamma rays

technetium-99m