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Tritium (from Ancient Greek τρίτος (trítos) 'third') or hydrogen-3 (symbol T or 3 H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.3 years. The tritium nucleus (t, sometimes called a triton) contains one proton and two neutrons, whereas the nucleus of the common isotope hydrogen-1 (protium) contains one proton and no neutrons, and that of non-radioactive hydrogen ...
Half-life (symbol t ½) is the time required for a quantity (of substance) to reduce to half of its initial value.The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive.
This value is in the denominator of the decay correcting fraction, so it is the same as multiplying the numerator by its inverse (), which is 2.82. (A simple way to check if you are using the decay correct formula right is to put in the value of the half-life in place of "t".
So, for example, digoxin has a half-life (or t 1 / 2 ) of 24–36 h; this means that a change in the dose will take the best part of a week to take full effect. For this reason, drugs with a long half-life (e.g., amiodarone , elimination t 1 / 2 of about 58 days) are usually started with a loading dose to achieve their desired ...
The half-life of this isotope is 6.480 days, [2] which corresponds to a total decay constant of 0.1070 d −1. Then the partial decay constants, as computed from the branching fractions, are 0.1050 d −1 for ε/β + decays, and 2.14×10 −4 d −1 for β − decays. Their respective partial half-lives are 6.603 d and 347 d.
The half-life, t 1/2, is the time taken for the activity of a given amount of a radioactive substance to decay to half of its initial value. The decay constant, λ "lambda", the reciprocal of the mean lifetime (in s −1), sometimes referred to as simply decay rate.
In chemistry, the decay technique is a method to generate chemical species such as radicals, carbocations, and other potentially unstable covalent structures by radioactive decay of other compounds. For example, decay of a tritium -labeled molecule yields an ionized helium atom, which might then break off to leave a cationic molecular fragment.
The decay scheme of a radioactive substance is a graphical presentation of all the transitions occurring in a decay, and of their relationships. Examples are shown below. It is useful to think of the decay scheme as placed in a coordinate system, where the vertical axis is energy, increasing from bottom to top, and the horizontal axis is the proton number, increasing from left to right.