There are two radioactive substances A and B. Decay constant of B is two times that of A. Initially both have equal numbr of nuclei. After n half lives of A, rate of disintegration of both are equal. Find the value of n.

Two radioactive nuclei X and Y initially contain an equal number of atoms.Their half life is 1 hour and 2 hours respectively.Calculate ratio of their rates of disintegration after two hours.

Radioactive element A are being produced at a constant rate alpha . The element has a decay constant lambda . At time t=0, there are N_0 nuclei of the element. If alpha=2N_0lambda , calculate the number of nuclei of A after one half life of A and also limiting value of N as t rarr infty .

If ax^(2)-bx+5=0 does not have two distinct real roots, then find the minimun value of 5a+b.

In a gaseous reaction A+2B iff 2C+D the initial concentration of B was 1.5 times that of A. At equilibrium the concentration of A and D were equal. Calculate the equilibrium constant K_(C) .

Radioactive disintegration is a first order reaction and its rate depends only upon the nature of nucleus and does not depend upon external factors like temperature and pressure. The rate of radioactive disintegration (Activity) is represented as -(dN)/(dt)=lambdaN Where lambda= decay constant, N= number of nuclei at time t, N_(0) =intial no. of nuclei. The above equation after integration can be represented as lambda=(2.303)/(t)log((N_(0))/(N)) Calculate the half-life period of a radioactive element which remains only 1//16 of its original amount in 4740 years: a) 1185 years b) 2370 years c) 52.5 years d) none of these

Radioactive disintegration is a first order reaction and its rate depends only upon the nature of nucleus and does not depend upon external factors like temperature and pressure. The rate of radioactive disintegration (Activity) is represented as -(dN)/(dt)=lambdaN Where lambda= decay constant, N= number of nuclei at time t, N_(0) =initial no. of nuclei. The above equation after integration can be represented as lambda=(2.303)/(t)log((N_(0))/(N)) Half-life period of U is 2.5xx10^(5) years. In how much time will the amount of U^(237) remaining be only 25% of the original amount ? a) 2.5xx10^(5) year b) 1.25xx10^(5) years c) 5xx10^(5) years d) none of these

A radioactive sample decays by simultaneous emission of two particles having respective half-lives of 1,620 years and 810 years. After what time, one fourth of the sample will be left behind?

Radioactive disintegration is a first order reaction and its rate depends only upon the nature of nucleus and does not depend upon external factors like temperature and pressure. The rate of radioactive disintegration (Activity) is represented as -(dN)/(dt)=lambdaN Where lambda= decay constant, N= number of nuclei at time t, N_(0) =intial no. of nuclei. The above equation after integration can be represented as lambda=(2.303)/(t)log((N_(0))/(N)) What is the activity in Ci (curie) of 1.0mole plutonium -239 ? (t_(1//2)=24000 years) a) 1.49 Ci b) 14.9 Ci c) 5.513xx10^(11) Ci d) None of these