Does radioactive decay randomly or at a predictable rate?

Question

please be brief in answering but accurate. please and thank you.

Answer 1

The predicted figure is accurate but its accuracy depends on the size of the sample.The half life of an atomic species is an average figure based on a reasonably sized sample with a huge number of atoms. It's based upon the probability that any given atom will decay at a given time. For instance scientists can predict that a coin has a 50/50 chance of landing heads or tails when flipped. This means that if you flipped the coin 1000 times you could be reasonably certain that you would get close to 500 tails and 500 heads. This doesn't mean that if you flipped it four times you would get 2 heads and 2 tails each time. It's the same with the rate of decay. The decay occurs randomly in that scientists cannot predict when any given atom will decay anymore than you can predict exactly which flips will result in heads or tails. But the more atoms a sample has the more accurate the predicted rate of decay (half life).

Answer 2

Every radioactive isotope has a measureable, predictable decay rate (called a "half-life") meaning that within the half-life timeframe for that specific isotope, half of the nuclei will have decayed to some other element.
So if a radioactive isotope has a half life of 10 years, then after 10 years half of the sample will have decayed to something else, leaving only half of the original sample still remaining as the radioactive isotope.

Answer 3

radioactive decay is predictable and constant

Answer 4

http://en.wikipedia.org/wiki/Radioactive_decay