The answer is (4), (3) is merely a change in composition, thus not chemical but physical.
Answer: (4).
Answer:
[Ar] 4s2 3d5 paramagnetic
Explanation:
Half-life is the length of time it takes for half of the radioactive atoms of a specific radionuclide to decay. A good rule of thumb is that, after seven half-lives, you will have less than one percent of the original amount of radiation.
<h3>What do you mean by half-life?</h3>
half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive.
<h3>What affects the half-life of an isotope?</h3>
Since the chemical bonding between atoms involves the deformation of atomic electron wavefunctions, the radioactive half-life of an atom can depend on how it is bonded to other atoms. Simply by changing the neighboring atoms that are bonded to a radioactive isotope, we can change its half-life.
Learn more about half life of an isotope here:
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Answer:
NiO Does Not Dissolve In An Aqueous Solution Of NaNO3.
Explanation: