Radiation and Decay
Half Lives
Decay Reactions
Atom and Isotope Structure
100
Which type of decay produces the weakest radiation?
Alpha
100
After one half life, what percentage of radioactive material would still be present?
50% or 0.5 or 1/2
100
Provide the missing isotope.
15562Sm -> 42 He + _____
15160Nd
100
If an atom has 20 protons, 21 Neutrons, and 18 Electrons, What is its mass Number?
Mass Number = 41
200
Which type of decay emits dangerous electromagnetic waves like X-rays?
Gamma
200
You have 400 radioactive isotopes with a half life of 2 minutes. How many radioactive isotopes are still present after 8 minutes?
25 Radioactive Isotopes
200
Provide the missing isotope.
16767Ho -> 0-1e + ___
16768Er
200
Which has more neutrons, 24Na or 24Mg?
24Na
300
Which type of decay increases the atomic number by 1 in a decay reaction?
Beta
300
An unknown radioactive substance completes 3 half lives in 45 minutes. How long is one half life of this unknown substance?
15 Minutes
300
Provide the missing isotope.
23590Th -> 23188Ra + _______
42He
300
Which has more neutrons 45Ca or 46Ti?
45Ca
400
What instrument is used to measure radiation exposure?
Geiger Counter
400
You obtain a radioactive substance with a half life of 10 minutes. After 30 minutes, you have 5 grams remaining. What was the original mass?
40 Grams
400
13153I -> 13154Xe + _____
0-1e
400
Write the nuclear symbol for an element with 4 protons, 6 neutrons and 4 electrons.
104Be
500
What form of radioactive decay does not result in transmutation?
Gamma
500
Using the graph, what is the half life of iodine-131 in days?
8 Days
500
24495Am goes through a decay series of Alpha, Alpha, Beta. What would the final isotope be?
23692U
500
Isotopes of the same element have the same number of _______ and a different number of ________
Protons;Neutrons
600
Which particle can be stopped by a piece of aluminum foil or plastic but not by a piece of paper?
Beta
600
How many half lives are required before less than 5% of the radioactive substance remains?
5 Half Lives
600
21082Pb goes through a decay series of Beta, Alpha, Beta. What would the final isotope be?
20682Pb
600
Write the name following isotope in ALL 3 different ways and isotope can be written.
10B, B-10, Boron-10