Radioactive disintergation always follow `I` order kinetics and is independent of all external factors and is represented by the relation `N = N_(0) e^(-lambda t)` where `lambda` is decay constant and `N` atoms are left at time `t`. The radioactive nature of element is expressed in terms of average life numerically equal to decay constant `(1//lambda)` however all the radioactive do not lose their radioactive nature in thier average life. The radioactive emission involves `alpha, beta` particles as well as `gamma-` rays.The penertrating power order is `alpha lt beta lt gamma`. The emissions can perntrate even thick steel walls but are however unable to penttrate `Pb` blocks. The `S` unit fo rate of decay is `dps`.
The number of `beta-` particles emitted during the change, `._(a)^(c)X rarr ._(d)^(b) Y` is:

Options

A. `(a-b)/(4)`
B. `d + [(a-b)/(2)] + c`
C. `d + [(c - b)/(2)] -a`
D. `d + [(a-b)/(2)] - c`

Answer

`c`

Explanation

`._(a)^(c)X rarr ._(d)^(b)Y + n ._(2)^(4)Y + n ._(2)^(4)He + m._(-1) e^(0)`
Equating mass no. `c = b + 4n + 0`
`:. N = (c-b)/(4)`
Equating at. No, `a = d + 2n + (-m)`
`:. M = d - a + (2(c-b))/(4) = d - a + [(c-b)/(2)]`