0
= 0.693 / T1/2 Nt = N0e(-lt)
where N0 is the starting number of nuclei, Nt is the number of nuclei remaining after timet, l is the decay constant, and e = 2.718. The units for the decay constant would be s-1 (or sometimes expressed in disintegrations per second) if the half-life is expressed in seconds. This relationship expresses radioactive decay based on statistics and probability, from an examination of the behaviour of a large number of individual situations. Note that it does not give any indication when a particular nucleus will undergo decay, but only the amount of time needed for a certain proportion of the nuclei in the sample to decay.
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Why is lead found in all deposits of uranium ores?
Uranium has a half life of 5,600 years. After that period, one half of the uranium becomes lead. That is why lead is found in uranium deposits.
How much cesium half life 2 years would remain from a 10 g sample after 6 years?
The formula for finding the amount of radio active substance that remainsafter decomposition is A = N(1/2) ^y, where A is the mass remaining, N is the original mass of a radioactive sample and y is the number of half life. In this case, N = 10 g and y = 6/2 = 3. So A is given by 10 x (1/2)^3, which is 10 x 1/2 x1/2 x 1/2 = 1.25 grams.
What is the half life of the earth's magnetic field?
Magnetic field doesnot have a half life. Elements have half life.
How much of a 400-gram sample of K40 is left after 2 half-lives?
After the first half-life, you will have one half of the starting amount. After a second half-life period, you'll be down to one quarter. Of the part that radioactively decays, about 11% of it will decay to 40Ar, and the remainder to 40Ca. Of your total sample of ordinary potassium, only 0.012% will be 40K. The half-life of 40K is about 1.3x109 years.
Calcium phosphate formula?
CaPO4 the 4 is a subsript( on the bottom half)
What is an isotope that the time it takes it to decay to half its original mass?
c.half-life
Is a period of an element the amount of time it takes for half of a radioactive isotope to decay?
False- the period is the horizontal row the element is in
What is the simple formula in calculating the half life of protactinium-234?
The half life is not calculated, but experimentally measured. The half life of Pa 234 is 6,75 hours.
What is Na2503 formula?
The formula is Sodium-55. It is a radioisiotpe with half life 7.3 seconds.
What is the half life of neptunium 238 over a period of 10 years?
The half life of neptunium-238 is 2,117 days.
How old in years is a fossil sample that has 12.5 percent C-14?
The half-life of Carbon-14 is 5,730 years. As such for the carbon-14 to decay from 100% to 12.5% it would take three times the half-life of the material.100% (1st half life decay period) 50% (2nd half life decay period) 25% (3rd half life decay period) 12.5%.Therefore = 5730 x 3 = 17,190 years.
What does it mean to have a half life?
A half life means the time required for something to fall to half its initial value. The original term was used by Ernest Rutherford's discovery of the principle in 1907 as "half life period," but was shortened to "half life," in the 1950's.
Which element has Highest half life period?
i guess it's Tellurium 128, with a half life of 2.2e24; you may consider it a stable isotope as well.
What is the half life of the radioactive isotope?
The half life is the period of time it takes radioactive decay to transmute one half of the isotope present at the start of the period to a different isotope, usually an isotope of a different element. This period of time is different for different isotopes, with known isotope half lives ranging from femtoseconds to many billions of years.
Does The half-life of a material increases with the amount of material present?
The half-life is a fixed period of time: the average time it will take for one of every two atoms to decay to another isotope or element. So no matter how much of a given radioactive isotope that you start with, only one-half of it will still be that isotope after a single half-life period. Likewise only half of that remaining material will be the same isotope after another half-life period. Of course, some of the atoms will be decaying all the time, so the half-life is only a convenient way to define the quantity at any given time.
Does the half-life of a material increase with the amount of material present?
The half-life is a fixed period of time: the average time it will take for one of every two atoms to decay to another isotope or element. So no matter how much of a given radioactive isotope that you start with, only one-half of it will still be that isotope after a single half-life period. Likewise only half of that remaining material will be the same isotope after another half-life period. Of course, some of the atoms will be decaying all the time, so the half-life is only a convenient way to define the quantity at any given time.
The time it takes for half of the radioactive element to decay is the element's what?
The time it takes for half the atoms in a sample of a radioactive element to decay is called the half life.
