Platinum has 38 known isotopes, ranging from 78166Pt to 78203Pt. Of these, five are stable, one has a half-life of 6.5x1011 years, and all the others are relatively short, some being very, very short. I will show the longest lived, because you did not specify which one you were interested in.
78190Pt --> Alpha --> T1/2 = 6.5x1011 years --> 76186Os + 24He2+
All nuclear decay is spontaneous.
That depends on the nuclear decay type. For gamma decay, the identity does NOT change, but for alpha and beta, it does.
Natural chromium is stable and does not decay/
Matter can be made to undergo nuclear decay in reactors, but it is a process that occurs spontaneously in nature.
zeyta
I do not see an isotope of iridium that does alpha decay. There is an interactive link to isotopes below. (Perhaps I am missing it.)
what are the forms of nuclear decay
nuclear decay, such as alpha decay or beta decay.
All nuclear decay is spontaneous.
Alpha nuclear decay
yep, sure are
The rate of nuclear decay increases as the temperature of a radioactive sample increases. This is due to the increased kinetic energy of the nuclei at higher temperatures, which facilitates interactions that lead to nuclear decay.
Nuclear fusion and nuclear fission are processes that involve nuclear reactions but are not examples of radioactive decay. Chemical reactions, such as burning wood, do not involve nuclear processes and are also not examples of radioactive decay.
That depends on the nuclear decay type. For gamma decay, the identity does NOT change, but for alpha and beta, it does.
radioactive decay
Natural chromium is stable and does not decay/
During the nuclear decay of Ne-19, a positron is emitted.