Nuclei — DPP 2

20 NEET questions from Nuclei, with answers and explanations. Attempt it as a timed test to get scoring, accuracy breakdown and mistake tracking.

Attempt this test free 20 questions · 30 minutes · +80 marks
1
Consider the nuclear reaction:
$\mathrm { X } ^ { 200 } \rightarrow \mathrm {~A} ^ { 110 } + \mathrm { B } ^ { 90 } + \text { Energy }$
The binding energy per nucleon for $\mathrm { X } ^ { 200 } , \mathrm {~A} ^ { 110 } , \mathrm {~B} ^ { 90 }$ are respectively 7.4 MeV, 8.2 MeV and 8.2 Mev. The energy released is
  1. A 200 MeV
  2. B 160 MeV
  3. C 110 MeV
  4. D 90 MeV
Show answer

Correct answer: B

2
Two nuclei have their mass number in the ratio of 1 : 3. The ratio of their nuclear densities would be
  1. A $(3)^{1 / 3}: 1$
  2. B 1 : 1
  3. C 1 : 3
  4. D 3 : 1
Show answer

Correct answer: B

3
The binding energy per nucleon of deuterium and helium nuclei are 1.1 MeV and 7 MeV respectively. When two deuterium nuclei fuse to form a helium nucleus the energy released in the fusion is:
  1. A 24.6 MeV
  2. B 25.1 MeV
  3. C 22.3 MeV
  4. D 23.6 Mev
Show answer

Correct answer: D

4
Assertion: Nuclear density is almost same for all nuclei.
Reason: The radius (r) of a nucleus depends only on the mass number (A) as r ∝ A$^{1/3}$.
  1. A Both Assertion and Reason are True and the Reason is a correct explanation of the Assertion
  2. B Both Assertion and Reason are True but Reason is not a correct explanation of the Assertion
  3. C Assertion is True but the Reason is False
  4. D Assertion and Reason are False
Show answer

Correct answer: A

5
Energy released as mass of 2 amu is converted into energy is
  1. A $1.5 \times 10 ^ { - 10 } \mathrm {~J}$
  2. B $3 \times 10 ^ { - 10 } \mathrm {~J}$
  3. C 1863 J
  4. D 931.5 MeV
Show answer

Correct answer: B

6
The ratio of the nuclear radii of the gold isotope ${ } _ { 79 } ^ { 197 } \mathrm { Au }$ and silver isotope ${ } _ { 47 } ^ { 107 } \mathrm { Ag }$ is:
  1. A 1.22
  2. B 0.216
  3. C 4
  4. D 0.612
Show answer

Correct answer: A

7
If the speed of light were 2/3 of its present value, the energy released in a given atomic explosion will be decreased by a fraction:
  1. A 2/3
  2. B 4/9
  3. C 3/4
  4. D 5/9
Show answer

Correct answer: D

8
A deutron is bombarded on ${ } _ { 8 } \mathrm { O } ^ { 16 }$ nucleus then α-particle is emitted. The product nucleus is
  1. A ${ } _ { 7 } \mathrm {~N} ^ { 13 }$
  2. B ${ } _ { 5 } \mathrm {~B} ^ { 10 }$
  3. C ${ } _ { 4 } \mathrm { Be } ^ { 9 }$
  4. D ${ } _ { 7 } \mathrm {~N} ^ { 14 }$
Show answer

Correct answer: D

9
Nuclear Forces are:
  1. A Short ranged attractive and charge independent
  2. B Short ranged attractive and charge dependent
  3. C Long ranged attractive and charge independent
  4. D Long ranged attractive and charge dependent
Show answer

Correct answer: A

10
Assertion: Fast-moving neutrons do not cause fission of a uranium nucleus.
Reason: A fast-moving neutron spends very little time inside the nucleus.
  1. A Both Assertion and Reason are True and the Reason is a correct explanation of the Assertion.
  2. B Both Assertion and Reason are True but Reason is not a correct explanation of the Assertion
  3. C Assertion is True but the Reason is False
  4. D Assertion and Reason are False
Show answer

Correct answer: A

11
The binding energies of the nuclei A and B are $\mathrm { E } _ { \mathrm { a } }$ and $\mathrm { E } _ { \mathrm { b } }$ respectively. Three nuclei of the element B fuse to give one nucleus of element 'A' and an energy 'Q' is released. Then $E _ { a } , E _ { b } , Q$ are related
  1. A $E _ { a } - 3 E _ { b } = Q$
  2. B $E _ { b } - 3 E _ { a } = Q$
  3. C $E _ { a } + 3 E _ { b } = Q$
  4. D $E _ { b } + 3 E _ { a } = Q$
Show answer

Correct answer: A

12
The nucleus which has radius one third of the radius of $\mathrm { Os } ^ { 189 }$ is:
  1. A $\mathrm { Be } ^ { 9 }$
  2. B $\mathrm { Li } ^ { 7 }$
  3. C $\mathrm { F } ^ { 19 }$
  4. D $\mathrm { Cl } ^ { 2 }$
Show answer & explanation

Correct answer: B

Let nucleus be ${ }_{z} \mathrm{X}^{\mathrm{A}}$
$\begin{array}{l}\therefore \frac{\mathrm{R}_{\mathrm{x}}}{\mathrm{R}_{\mathrm{Os}}}=\left(\frac{\mathrm{A}}{189}\right)^{1 / 3} \\ \therefore \frac{1}{3}=\left(\frac{\mathrm{A}}{189}\right)^{1 / 3} \\ \mathrm{~A}=\frac{189}{27}=7\end{array}$
Therefore, option (B) is the correct answer.
13
The mass defect in a nucleus is 3.5 amu. Then the binding energy of the nucleus is
  1. A 32.58 MeV
  2. B 325.85 MeV
  3. C 3260.25 MeV
  4. D 3.258 MeV
Show answer

Correct answer: C

14
In the nucleus of ${ } _ { 11 } \mathrm { Na } ^ { 23 }$, the number of protons, neutrons and electrons are
  1. A 11, 12, 0
  2. B 23, 12, 11
  3. C 12, 11, 0
  4. D 23, 11, 12
Show answer

Correct answer: A

15
In nuclear fission, 0.1% mass is converted into Energy. The energy released in the fission of 1kg mass is
  1. A $2.5 \times 10^{5} \mathrm{kWh}$
  2. B $2.5 \times 10^{7} \mathrm{kWh}$
  3. C $2.5 \times 10^{9} \mathrm{kWh}$
  4. D $2.5 \times 10^{-7} \mathrm{kWh}$
Show answer

Correct answer: B

16
In a fission process, nucleus A divides into two nuclei B and C, their binding energies being $\mathrm { E } _ { \mathrm { a } } , \mathrm { E } _ { \mathrm { b } }$ and $\mathrm { E } _ { \mathrm { c } }$ respectively. Then:
  1. A $E _ { b } + E _ { c } = E _ { a }$
  2. B $\mathrm { E } _ { \mathrm { b } } + \mathrm { E } _ { \mathrm { c } } > \mathrm { E } _ { \mathrm { a } }$
  3. C $E _ { b } + E _ { c } < E _ { a }$
  4. D $\mathrm { E } _ { \mathrm { b } } , \mathrm { E } _ { \mathrm { c } } = \mathrm { E } _ { \mathrm { a } }$
Show answer

Correct answer: B

17
If M is the atomic mass and A is the mass number, then packing fraction is given by:
  1. A $\frac { \mathrm { A } } { \mathrm { M } - \mathrm { A } }$
  2. B $\frac { \mathrm { A } - \mathrm { M } } { \mathrm { A } }$
  3. C $\frac { \mathrm { M } } { \mathrm { M } - \mathrm { A } }$
  4. D $\frac { \mathrm { M } - \mathrm { A } } { \mathrm { A } }$
Show answer

Correct answer: D

18
The energy required to separate the typical middle mass nucleus ${ } _ { 50 } { } ^ { 120 } \mathrm { Sn }$ into its constituent nucleons is (Mass of ${ } _ { 50 } { } ^ { 120 } \mathrm { Sn } = 119.902199 \mathrm { u }$; mass of ${ } _ { 1 } ^ { 1 } \mathrm { H } = 1.00783 \mathrm { u }$ and mass of neutron $= 1.008665 \mathrm { u }$ )
  1. A 951 MeV
  2. B 805 MeV
  3. C 1021 MeV
  4. D 1212 MeV
Show answer

Correct answer: C

19
Thorium isotope ${ } _ { 90 } \mathrm { Th } ^ { 232 }$ emits some $\alpha$-particles and some $\beta$-particles and gets transformed into lead isotope ${ } _ { 82 } \mathrm {~Pb} ^ { 200 }$. Find the number of $\alpha$ and $\beta$ particles emitted.
  1. A $\mathrm { N } _ { \alpha } = 6 , \mathrm {~N} _ { \beta } = 6$
  2. B $\mathrm { N } _ { \alpha } = 2 , \mathrm {~N} _ { \mathrm { B } } = 2$
  3. C $\mathrm { N } _ { \alpha } = 4 , \mathrm {~N} _ { \beta } = 4$
  4. D $\mathrm { N } _ { \alpha } = 8 , \mathrm {~N} _ { \beta } = 8$
Show answer

Correct answer: D

20
The constituents of atomic nuclei are believed to be
  1. A neutrons and protons
  2. B protons only
  3. C electrons and protons
  4. D electrons, protons and neutrons
Show answer

Correct answer: A

Attempt this as a timed test

Reading answers is not the same as sitting the paper. Attempt it timed and you get your score, per-question timing, and the mistakes tracked for revision.

Start free

More Nuclei tests

Nuclei — DPP 1 20 Q Nuclei — DPP 3 20 Q
All Nuclei tests →