the amount of time it takes for HALF of a given radioactive substance to decay into a more stable isotope.
What is a half-life?
The alpha decay of Pu-239 forms an alpha particle and what else?
U-235
I-131 has a half life of 8 days. How much of a 14 g sample is present after 16 days?
3.5 g
What type of decay is involved in Bi-214 becoming Po-214?
beta
this type of decay results in the emission of radiation that has no mass or protons.
What is gamma?
The half life of thorium-234 is 24 days. How much time must pass for 1/8th of a 100 gram sample to remain?
What is 72 days?
Neutron bombardment of plutonium-239 yields americum-240 and another particle. Identify the other particle produced.
What is an electron or beta particle?
the mass of the starting nucleus undergoing alpha decay decreases by this much
What is 4?
In 1995, a 100 g of Co-60 was stored. In 2010, 12.5 g remained. What is its half-life?
5 years
The number of neutrons in Uranium-240
What is 148?
Determine the missing particle:
146C -->_____ + 0-1e
Nitrogen - 14
You found a 30 gram sample of volcanic rock that contains Potassium-40.
If ORIGINALLY there had been 120 grams of this rock when it formed 2.6 billion years ago, what is the half life of Potassium-40?
What is 1.3 billion years?
What is average atomic mass of Lithium if 7.42% exists as Li-6 and 92.58% exists as Li-7?
What is 6.9 amu?
Determine the missing particle and type of decay:
23994Pu --> 42He + _____
Uranium - 235