In an `alpha`-decay

What is alpha -decay? What is the consequence of an alpha -decay on a radioactive element ?

How do the mass number and atomic number change in alpha -decay? A nucleus X becomes nucleus Y as a result of alpha -decay. Represent it by an equation.

The decay constant for an alpha- decay of Th^(232) is 1.58xx10^(-10)s^(-1) . How many alpha- decays occur from 1 g sample in 365 days ?

The decay constant for an alpha- decay of Th^(232) is 1.58xx10^(-10)s^(-1) . How many alpha- decays occur from 1 g sample in 365 deys ?

Assertion: ""_2X^(A) undergoes 2 alpha -decay and the daughter product is ""_(z-4)Y^(A-8) Reason: In alpha -decay the mass number decreases by 4 and atomic number decreases by 2.

Explain alpha - decay ?