Advertisements
Advertisements
प्रश्न
A radioactive nucleus 'A' undergoes a series of decays as given below:
The mass number and atomic number of A2 are 176 and 71 respectively. Determine the mass and atomic numbers of A4 and A.
उत्तर
The mass number and atomic number of A4 is 172 and 69, respectively.
The mass number and atomic number of A is 180 and 74, respectively.
APPEARS IN
संबंधित प्रश्न
Obtain the relation between the decay constant and half life of a radioactive sample.
A source contains two phosphorous radio nuclides `""_15^32"P"` (T1/2 = 14.3d) and `""_15^33"P"` (T1/2 = 25.3d). Initially, 10% of the decays come from `""_15^33"P"`. How long one must wait until 90% do so?
Define the activity of a given radioactive substance. Write its S.I. unit.
The decay constant of a radioactive sample is λ. The half-life and the average-life of the sample are respectively
Lithium (Z = 3) has two stable isotopes 6Li and 7Li. When neutrons are bombarded on lithium sample, electrons and α-particles are ejected. Write down the nuclear process taking place.
57Co decays to 57Fe by β+- emission. The resulting 57Fe is in its excited state and comes to the ground state by emitting γ-rays. The half-life of β+- decay is 270 days and that of the γ-emissions is 10−8 s. A sample of 57Co gives 5.0 × 109 gamma rays per second. How much time will elapse before the emission rate of gamma rays drops to 2.5 × 109per second?
Obtain a relation between the half-life of a radioactive substance and decay constant (λ).
Before the year 1900 the activity per unit mass of atmospheric carbon due to the presence of 14C averaged about 0.255 Bq per gram of carbon.
(a) What fraction of carbon atoms were 14C?
(b) An archaeological specimen containing 500 mg of carbon, shows 174 decays in one hour. What is the age of the specimen, assuming that its activity per unit mass of carbon when the specimen died was equal to the average value of the air? The half-life of 14C is 5730 years.
Obtain an expression for the decay law of radioactivity. Hence show that the activity A(t) =λNO e-λt.
The half-life of the radioactive substance is 40 days. The substance will disintegrate completely in
