Advertisements
Advertisements
प्रश्न
Find the Q-value and the kinetic energy of the emitted α-particle in the α-decay of `""_86^220"Rn"`.
Given `"m"(""_88^226"Ra")` = 226.02540 u, `"m"(""_86^222 "Rn")` = 222.01750 u,
`"m"(""_86^220 "Rn")`= 220.01137 u, `"m"(""_84^216 "Po")`= 216.00189 u.
Advertisements
उत्तर
Alpha particle decay of `(""_86^220"Rn")` is shown by the following nuclear reaction.
\[\ce{^220_86Rn -> ^216_84Po + ^4_2He}\]
It is given that:
Mass of `(""_86^220 "Rn")` = 220.01137 u
Mass of `(""_84^216 "Po")` = 216.00189 u
∴ Q-value = [220.01137 - (216.00189 +.00260)] × 931.5
≈ 641 MeV
Kinetic energy of the α-particle = `((220-4)/220) xx 6.41`
= 6.29 MeV
संबंधित प्रश्न
Two stable isotopes of lithium `""_3^6"Li"` and `""_3^7"Li"` have respective abundances of 7.5% and 92.5%. These isotopes have masses 6.01512 u and 7.01600 u, respectively. Find the atomic mass of lithium.
The three stable isotopes of neon: `""_10^20"Ne"`, `""_10^21"Ne"` and `""_10^22"Ne"` have respective abundances of 90.51%, 0.27% and 9.22%. The atomic masses of the three isotopes are 19.99 u, 20.99 u and 21.99 u, respectively. Obtain the average atomic mass of neon.
In a periodic table the average atomic mass of magnesium is given as 24.312 u. The average value is based on their relative natural abundance on earth. The three isotopes and their masses are `""_12^24Mg` (23.98504u), `""_12^25 Mg` (24.98584u) and `""_12^26Mg` (25.98259u). The natural abundance of `""_12^24 Mg` is 78.99% by mass. Calculate the abundances of other two isotopes.
What do you mean by polar molecules and non-polar molecules? Give ‘one’ example each.
Name a material which is used in making control rods in a nuclear reactor.
Potassium-40 can decay in three modes. It can decay by β−-emission, B*-emission of electron capture. (a) Write the equations showing the end products. (b) Find the Q-values in each of the three cases. Atomic masses of `""_18^40Ar` , `""_19^40K` and `""_20^40Ca` are 39.9624 u, 39.9640 u and 39.9626 u respectively.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
The atomic mass of Uranium `""_92^238"U"` is 238.0508 u, while that of Thorium `""_90^234"Th"` is 234.0436u, and that of Helium `""_2^4"He"` "is 4.0026u. Alpha decay converts `""_92^238"U"` into `""_92^234"Th"` as, shown below:
`""_92^238"U" -> ( ""_90^234"Th" + ""_2^4"He" + "Energy" )`
What is a neutrino?
Nuclides with same neutron number N but different atomic number Z are called ______.
A vessel contains oil (density 0.8 g/cm3) over mercury (density 13.6 g/cm3). A sphere of homogeneous composition floats with half its volume immersed in mercury and the other half in oil. The density of the material of the sphere in g/cm3 is ______.
The mass number of a nucleus is equal to the number of:-
Are the nucleons fundamental particles, or do they consist of still smaller parts? One way to find out is to probe a nucleon just as Rutherford probed an atom. What should be the kinetic energy of an electron for it to be able to probe a nucleon? Assume the diameter of a nucleon to be approximately 10–15 m.
Distinguish between isotopes and isobars.
James Chadwick, in 1932 studied the emission of neutral radiations when Beryllium nuclei were bombarded with alpha particles. He concluded that emitted radiations were neutrons and not photons. Explain.
Mass numbers of two nuclei are in the ratio of 4 : 3. Their nuclear densities will be in the ratio of ______.
Assertion (R): Fusion of hydrogen nuclei into helium nuclei is the source of energy of all stars.
Reason (R): In fusion heavier nuclei split to form lighter nuclei.
Energy equivalent of 1 amu is:
