Which has maximum half-life?

Bismuth-209 (²⁰⁹Bi) is the isotope of bismuth with the longest known half-life of any radioisotope that undergoes α-decay (alpha decay). It has 83 protons and a magic number of 126 neutrons, and an atomic mass of 208.9803987 amu (atomic mass units).

What has the highest half-life?

Uranium is a radionuclide that has an extremely long half-life. Naturally occurring uranium-238 present in the Earth's crust has a half-life of almost 4.5 billion years.

Which of the following is a maximum half-life period?

The U-238 isotope is the longest lived with a half-life of 4.5 billon years and constitutes more than 99% of the mass of natural uranium and half of its radioactivity.

Which element has infinite half-life?

Hydrogen is an element, the nucleus of which is made up of a single proton. The proton has never been observed to decay and a current estimate of the half-life of a proton is at least 1.67×1034 years. So, for all intents and purposes, hydrogen's half-life can be considered infinite.

Which radioactive substance has half-life?

The half-life of a radioactive isotope is the amount of time it takes for one-half of the radioactive isotope to decay. The half-life of a specific radioactive isotope is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.

GCSE Science Revision Physics "Half Life"

What is the longest and shortest half-life?

Copernicium 285 has the shortest half life, which is 5*10^-19 seconds. Longest is definitely uranium 238, over a billion years.

What makes a longer half-life?

Half-life is dependent on both clearance and volume of distribution, such that a decrease in clearance, as might be seen with a CYP1A2 or CYP2C19 substrate, or an increase in volume of distribution will prolong the half-life and lead to a longer dosage interval.

What does longest half-life mean?

A drug's half-life matters because: a short half-life usually means more withdrawal problems. a long half-life usually means fewer withdrawal problems.

Does carbon or uranium have a longer half-life?

The half-life of the slightly unstable uranium-238 is 4.5 billion years. Carbon-14 has a half-life of 5,730 years.

What is the longest half-life of radioactive waste?

Iodine-129 has the longest half-life, 15.7 million years, and due to its higher half life, lower fission fraction and decay energy it produces only about 1% the intensity of radioactivity as ⁹⁹Tc.

Does uranium have a long half-life?

All isotopes of uranium are radioactive, with most having extremely long half-lives. Half-life is a measure of the time it takes for one half of the atoms of a particular radionuclide to disintegrate (or decay) into another nuclear form. Each radionuclide has a characteristic half-life.

Does water have a half-life?

For example, the biological half-life of water in a human being is about 9 to 10 days, though this can be altered by behavior and other conditions.

What element has the fastest half-life?

You may wonder which naturally-occurring element has the shortest half-life. That would be francium, element 87, whose longest-lived isotope, francium-223, has a half-life of 22 minutes, decaying either into radium by beta decay or astatine by alpha emission.

Can half-life be infinite?

In the extreme limit of this approach, all of the electrons can be ripped off of a radioactive atom. For such an ion, there are no longer any electrons available to capture, and therefore the half-life of the electron capture radioactive decay mode becomes infinite.

What's the most radioactive element?

Radium was named for the Latin for a ray and proved to be the most radioactive natural substance ever discovered.

How radioactive is uranium?

Uranium is weakly radioactive and contributes to low levels of natural background radiation. The majority of background radiation occurs naturally and a small fraction comes from man-made elements. in the environment. Uranium is used in nuclear power generation.

What is the half-life of thorium?

Thorium's most stable isotope, thorium-232, has a half-life of about 14,050,000,000 years. It decays into radium-228 through alpha decay or decays through spontaneous fission.

How do we know the half-life of elements?

The half-life is then determined from the fundamental definition of activity as the product of the radionuclide decay constant, λ, and the number of radioactive atoms present, N. One solves for λ and gets the half-life from the relationship λ = ln2/T_1/2.

What has a half-life of 40 years?

Once the organism dies, however, it ceases to absorb carbon-14, so that the amount of the isotope in its tissues steadily decreases. Carbon-14 has a half-life of 5,730 ± 40 years (i.e., half the amount of the isotope present at any instant will undergo spontaneous disintegration during the succeeding 5,730 years).

Does carbon have a long half-life?

C has a half-life of 5,730 years. In other words, after 5,730 years, only half of the original amount of ¹⁴C remains in a sample of organic material.

How long does uranium stay?

Uranium undergoes radioactive decay very slowly. The half-life for U²³⁸ is 4.5 billion years. After one half-life, a container that originally held 10,000 kg of pure U²³⁸ would be reduced to 5,000 kg of U²³⁸, along with approximately 5,000 kg of associated daughter products.

Is carbon-14 half-life long?

The half-life of radiocarbon (14C) is 5700 ± 30 yr, which makes it particularly useful for dating in archaeology. However, only an exceptional hindrance of the beta decay from 14C to 14N—a so-called Gamow-Teller ß-decay—makes this half-life so long.

What is the half-life of iron?

Two radioactive isotopes of iron, namely, iron-59 (half-life 45 days) and iron-55 (half-life 3 years), have been used extensively for tracer investigations in medical and biological studies.

Do all elements have half-life?

Answer and Explanation: All elements have half-lives because all elements can have radioactive isotopes. However, even the stable isotopes of an element can break down over time.