Question

A neutron causes   90²³²Th to change according to the following reaction:   

0¹n +   90²³²Th ?   Z^AX + ?

The Z^AX nucleus subsequently undergoes ?^- decay, and its daughter does too. What is the atomic mass number of the final nucleus?

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Answer 1

Here,

A= Atomic Mass ( Total number of Neutrons + Protons in the nucleus of an atom);

Z= Atomic number (Equal to the number of Electrons)

In Beta-minus decay changes One Neutron into Proton.

So, Thorium232 absorbs that neutrons and changes to Thorium 233 (raising atomic mass by 1 unit).

Two of the Beta -minus decays raise the Atomic number from 90 to 92. ( Beta decay+ daughter ).

Atomic Mass number of the final Nucleus is 233 and it is a Fissianble nuclide Uranium233