Mass-energy and Nuclear Binding Energy

IMPORTANT

Mass-energy and Nuclear Binding Energy: Overview

This topic covers concepts, such as Equivalence of Mass and Energy, Equivalent Energy of 1 U Mass, Mass Spectrometer, Mass Defect, Binding Energy, Binding Energy per Nucleon, Dependence of Nuclear Stability on Binding Energy per Nucleon, etc.

Important Questions on Mass-energy and Nuclear Binding Energy

EASY
IMPORTANT

The plot of the binding energy per nucleon versus the mass number A for a large number of nuclei,  2A240  is shown in Fig. In which range the binding energy per nucleon is constant?

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EASY
IMPORTANT

The plot of the binding energy per nucleon versus the mass number A for a large number of nuclei,   2A240  is shown in Fig. In which range the binding energy per nucleon is constant?

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EASY
IMPORTANT

Calculate the energy released in MeV in the following nuclear reaction :<

92 238 U   90 234 Th+   2 4 He+Q

[Mass of   92 238 U = 238.05079 u]

Mass of   90 234 Th = 234.043630 u

Mass of   2 4 He  = 4.002600 u

1 u = 931.5 MeV

EASY
IMPORTANT

Calculate the binding energy per nucleon of  20 40 Ca nucleus.

Given:

Mass of  2040Ca=39.962589 u,

Mass of proton =1.007825 u,

1 u=931 MeVc2 and

Mass of neutron=1.008665 u

EASY
IMPORTANT

The value of binding energy per nucleon of   20 40 Ca nucleus is

Given:

Mass of   20 40 Ca nucleus =39.962589u

Mass of proton =1.007825u

Mass of neutron =1.008665u

and 1 u=931 MeV C-2

EASY
IMPORTANT

A neutron is absorbed by a   3 6 Li  nucleus with the subsequent emission of an alpha particle.

 L36i+n01H24e+H13+Q

Calculate the energy released, in MeV, in this reaction.

[Given: mass  36Li=6.015126u;   mass (neutron) =1.0086654 u;

Mass (alpha particle) =4.0026044 u and

Mass (tritium) =3.0100000 u.

[ Take  1 u=931 MeV c-2 ]

EASY
IMPORTANT

The binding energies per nucleon for deuteron (H21) and helium (He42) are 1.1 MeV and 7.0 MeV respectively. The energy released when two deuterons fuse to form a helium nucleus (He42) is

EASY
IMPORTANT

In the nuclear process, C611B511+β++X, X stands for _______

MEDIUM
IMPORTANT

Two deuterons undergo nuclear fusion to form a Helium nucleus. The energy released in this process is (given binding energy per nucleon for deuteron=1.1 MeV and for helium=7.0 MeV)

EASY
IMPORTANT

The mass of a 37Li nucleus is 0.042 u less than the sum of the masses of all its nucleons. The binding energy per nucleon of  37Li nucleus is nearly

EASY
IMPORTANT

Imagine that a reactor converts all the given mass into energy and that it operates at a power level of 109 watt. The mass of the fuel consumed per hour, in the reactor, will be:
(velocity of light, c is 3×10m s-1)

MEDIUM
IMPORTANT

The above is a plot of binding energy per nucleon Eb, against the nuclear mass M; A, B, C, D, E, correspond to different nuclei. Consider four reactions :

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(i) A+BC+ε
(ii) CA+B+ε
(iii) D+EF+ε and

(iv) FD+E+ε 

where ε is the energy released. In which reactions ε positive

HARD
IMPORTANT

Four hydrogen nuclei combine to form a helium nucleus. If the mass defect in the formation of helium is 0.5%  and one kg of hydrogen undergoes fusion to form helium, the energy released in kilowatt hour is

EASY
IMPORTANT

Two deuterons undergo fusion to form a helium nucleus as H21+H21He42+Q. Given binding energy per nucleon for H21 and He42 are 1.1 MeV and 7.00 MeV, respectively. The Q-value is

EASY
IMPORTANT

The voltage applied to an X-ray tube is 18 kV. The maximum equivalent mass of photon emitted by the X-ray tube will be:

EASY
IMPORTANT

The difference between the mass of a C612 nucleus and the sum of the masses of the individual nucleons is 0.1 u. Which of the following is approximately the binding energy of the nucleus?

EASY
IMPORTANT

A star consist of deuterons. It initially has 1040 deutrons. It produces energy by the processes

H21+H21H31+p
H21+H31H2e4+n
If the average power radiated by the star is 1.6 ×1016 watt and masses of nuclei are

MH21=3AMU,  M(P)M(n)1  AMU,
MH2e4=4AMU and use approximation,
energy equivalent to 1AMU1000MeV. Find the time in which the supply of deuteron in the star is exhausted.

EASY
IMPORTANT

A star has a supply of 1050 deuterons. It produces energy via a fusion reaction

H12+H12H13+p

and H12+H13He24+n

where masses of nuclei are

mH2=2.014 amu, m(p)=1.007 amu,

m(n)=1.008 amu and mHe4=4.001 amu

If the average power radiated by the star is 1016 W. The deuteron supply of the star is exhausted in a time of the order of (1 amu=931 MeV)

HARD
IMPORTANT

The mass of deuteron 1H2 nucleus is 2.0159403 u. If the masses of proton and neutron are 1.007275 u and 1.008667 u respectively, calculate the binding energy per nucleon.

EASY
IMPORTANT

Binding energy of a nucleus is,