A radioactive nucleus \(_{\mathrm{Z}}^{\mathrm{A}}\mathrm{X}\) undergoes spontaneous decay in the sequence \(_{\mathrm{Z}}^{\mathrm{A}}\mathrm{X}\rightarrow \mathrm{B}_{\mathrm{Z-1}}\rightarrow \mathrm{C}_{\mathrm{Z-3}}\rightarrow \mathrm{D}_{\mathrm{Z-2}}\) where \(\mathrm{Z}\) is the atomic number of element \(\mathrm{X}.\) The possible decay particles in the sequence are: 
1. \(\beta^{+}, ~\alpha, ~\beta^{-}\) 2. \(\beta^{-}, ~\alpha, ~\beta^{+}\)
3. \(\alpha, ~\beta^{-},~\beta^{+}\) 4. \(\alpha, ~\beta^{+},~\beta^{-}\)

Subtopic:  Types of Decay |
 74%
Level 2: 60%+
NEET - 2021
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A nucleus with mass number \(240\) breaks into fragments each of mass number \(120.\) The binding energy per nucleon of unfragmented nuclei is \(7.6~\text{MeV}\) while that of fragments is \(8.5~\text{MeV}.\) The total gain in the binding energy in the process is:

1. \(804~\text{MeV}\) 2. \(216~\text{MeV}\)
3. \(0.9~\text{MeV}\) 4. \(9.4~\text{MeV}\)
Subtopic:  Nuclear Binding Energy |
 65%
Level 2: 60%+
NEET - 2021
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What happens to the mass number and the atomic number of an element when it emits \(\gamma\text{-}\)radiation?

1. mass number decreases by four and atomic number decreases by two.
2. mass number and atomic number remain unchanged.
3. mass number remains unchanged while the atomic number decreases by one.
4. mass number increases by four and the atomic number increases by two.
Subtopic:  Types of Decay |
 84%
Level 1: 80%+
NEET - 2020
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In the given nuclear reaction, the element \(\mathrm{X}\) is: 
\({ }_{11}^{22} \mathrm{Na} \rightarrow \mathrm{X}+\mathrm{e}^{+}+\nu\)
1. \({ }_{12}^{22} \mathrm{Mg}\) 2. \({ }_{11}^{23} \mathrm{Na}\)
3. \({ }_{10}^{23} \mathrm{Ne}\) 4. \(_{10}^{22}\textrm{Ne}\)
Subtopic:  Types of Decay |
 68%
Level 2: 60%+
NEET - 2022
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A nucleus of mass number \(189\) splits into two nuclei having mass numbers \(125\) and \(64.\) The ratio of the radius of two daughter nuclei respectively is:
1. \(25:16\)
2. \(1:1\)
3. \(4:5\)
4. \(5:4\)
Subtopic:  Nucleus |
 83%
Level 1: 80%+
NEET - 2022
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When a uranium isotope \(_{92}^{235}\mathrm{U}\) is bombarded with a neutron, it generates \(_{36}^{89}\mathrm{Kr}\), three neutrons and:
1. \(_{40}^{91}\mathrm{Zr}\) 2. \(_{36}^{101}\mathrm{Kr}\)
3. \(_{36}^{103}\mathrm{Kr}\) 4. \(_{56}^{144}\mathrm{Ba}\)
Subtopic:  Nuclear Energy |
 85%
Level 1: 80%+
NEET - 2020
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The energy equivalent of \(0.5~\text g\) of a substance is:
1. \(4.5\times10^{13}~\text J\) 2. \(1.5\times10^{13}~\text J\)
3. \(0.5\times10^{13}~\text J\) 4. \(4.5\times10^{16}~\text J\)
Subtopic:  Mass-Energy Equivalent |
 65%
Level 2: 60%+
NEET - 2020
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\({ }_{82}^{290} X \xrightarrow{\alpha} Y \xrightarrow{e^{+}} Z \xrightarrow{\beta^{-}} P \xrightarrow{e^{-}} Q\)
In the nuclear emission stated above, the mass number and atomic number of the product \(Q\) respectively, are:
1. \(286,80\)
2. \(288,82\)
3. \(286,81\)
4. \(280,81\)
Subtopic:  Types of Decay |
 67%
Level 2: 60%+
NEET - 2024
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The ratio of nuclear densities and nuclear volumes of \(^{56}_{26}Fe\) and \(^{4}_{2}He\) are, respectively:
1. \(13:1\) and \(14:1\) 2. \(14:1\) and \(1:1\)
3. \(1:1\) and \(14:1\) 4. \(1:1\) and \(13:1\)
Subtopic:  Nucleus |
 79%
Level 2: 60%+
NEET - 2024
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An excited heavy nucleus \(^A_Z \mathrm{X}\) emits radiations in the following sequence:
\(^A_Z \mathrm{X}\rightarrow ^{A-4}_{Z-2}\mathrm{D_1}\rightarrow ^{A-4}_{Z-1}\mathrm{D_2}\rightarrow ^{A-8}_{Z-3}\mathrm{D_3}\rightarrow ^{A-8}_{Z-4}\mathrm{D_4}\rightarrow ^{A-8}_{Z-4}\mathrm{D_5}\)
where \(Z,A\) are the atomic and mass number of element \(\mathrm{X},\) respectively. The possible emitted particles or radiations in the sequence, respectively are: 
1. \(e^+, \alpha, e^-, \alpha , \gamma \) 2. \(e^-, \alpha, e^+, \alpha , \gamma \)
3. \(\alpha ,e^-, \alpha, e^+, \gamma \) 4. \(\alpha ,e^+, \alpha, e^-, \gamma \)
Subtopic:  Types of Decay |
 68%
Level 2: 60%+
NEET - 2024
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