A radioactive element x has half life of 30 days and will decay to become another new element Y..

a) calculate decay constant
b) how long it will take for 90% of the no.Of atom in radioisotope x to decay?

a.) Having decay constant as t=0.693/decay constant. Therefore decay constant=0.693/t (i.e time).

Decay constant=0.693/30
=0.02

a.) Having decay constant as t=0.693/decay constant. Therefore decay constant=0.693/t (i.e time).

Decay constant=0.693/30
=0.02

To answer these questions, we need to use the formula for radioactive decay:

N = N0 * e^(-λ * t)

where:
N = final number of atoms
N0 = initial number of atoms
λ = decay constant
t = time

a) To calculate the decay constant (λ), we can use the formula:

λ = ln(2) / t1/2

Given that the half-life (t1/2) of element x is 30 days, we can substitute it into the formula:

λ = ln(2) / 30

Calculating λ:

λ = 0.0231 (approximately)

Therefore, the decay constant (λ) for element x is 0.0231.

b) To find the time it takes for 90% of the atoms to decay, we can start by rearranging the radioactive decay formula:

N/N0 = e^(-λ * t)

Given that we want 90% of the atoms to decay, N/N0 will be 0.1. Substituting the values:

0.1 = e^(-0.0231 * t)

To solve for t (time), we need to take the natural logarithm (ln) of both sides:

ln(0.1) = -0.0231 * t

Now we can solve for t:

t = ln(0.1) / (-0.0231)

Calculating t:

t ≈ 100.93 days

Therefore, it will take approximately 100.93 days for 90% of the atoms in radioisotope x to decay.