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प्रश्न
The radioactive isotope D decays according to the sequence
If the mass number and atomic number of D2 are 176 and 71 respectively, what is (i) the mass number (ii) atomic number of D?
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उत्तर
An alpha (α) particle is a helium nucleus (`""_2^4He)`and a beta-minus decay (β−) is an emission of an electron.
The substance D2 can be represented as `""_71^176D_2`.
Hence,
(i) The mass number of D is 180.
(ii) The atomic number of D is 72.
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