Question
The halflife of a radioactive substance is against . Calculate the decay rate for atoms of the substance.

None of these



easy
Solution
According to Rutherford and Soddy law, the rate of radioactive decay at any time t is given by
where is decay constant and N is the number of atoms left at time t. If Tbe the halflife, then
.
Substituting this value of atoms in eq. (i), we get
.
SIMILAR QUESTIONS
The halflife of radon is 3.8 days. Calculate how mach radon will be left out of 1024 milligram after 38 days?
1 milligram radium has . Its halflife is 1620 years. How many radium atoms will disintegrate from 1 milligram of pure radium in 3240 years?
A sample of radioactive substance has 10^{6} radioactive nuclei. Its halflife time is 20 seconds. How many nuclei will remain after 10 seconds?
A sample contains 10^{–2} kg each of the two substances A and B with halflives 4 seconds and 8 seconds respectively. Their atomic weights are in the ratio of 1 : 2. Find the amounts of A and B after an interval of 16 seconds.
The halflife of radius is 1600 years. After how many years 25% of a radium block remains undecayed?
The halflife of polonium is 140 days. In what time will 15 g of polonium be disintegrated out of its initial mass of 16 g?
The activity of a radioactive element reduces to ^{th} of its original value in 30 years. Find the halflife and the decay constant of the element.
The halflife of thoriumX is 3.64 days. After how many days will 0.1 of the mass of a sample of the substance remain undecayed?
How much of 5.00 gram of polonium will decay in one year? The halflife of polonium is 138 days.
The halflife of against . Calculate the activity of 1 g sample of . Avogadro’s number is .