Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 2]
Exam
Concepts Of Physics MCQ Edition [Volume 2]
Subject
Physics
Chapter
The Nucleus

Concepts Of Physics MCQ Edition [Volume 2] · Physics · The Nucleus

Evaluate the minimum energy required to separate a proton from a...

Evaluate the minimum energy required to separate a proton from a nucleus containing ZZ protons and NN neutrons. Let MZ,NM_{Z, N} denote the mass of an atom with ZZ protons and NN neutrons in the nucleus, and MHM_H denote the mass of a hydrogen atom. This energy is termed the proton-separation energy.

Options

  1. AΔE=(MZ,N−1+MH−MZ,N)c2\Delta E = (M_{Z, N-1} + M_H - M_{Z, N}) c^2
  2. BΔE=(MZ,N−MZ−1,N−MH)c2\Delta E = (M_{Z, N} - M_{Z-1, N} - M_H) c^2
  3. CΔE=(MZ−1,N+MZ,N−MH)c2\Delta E = (M_{Z-1, N} + M_{Z, N} - M_H) c^2
  4. DΔE=(MZ−1,N+MH−MZ,N)c2\Delta E = (M_{Z-1, N} + M_H - M_{Z, N}) c^2

Correct answer

D. ΔE=(MZ−1,N+MH−MZ,N)c2\Delta E = (M_{Z-1, N} + M_H - M_{Z, N}) c^2

Step-by-step solution

The separation of a proton from a nucleus with ZZ protons and NN neutrons can be represented as:

Nucleus(Z,N)→(Z, N) \rightarrow Nucleus(Z−1,N)+(Z-1, N) + proton

The minimum energy required for this process is the proton-separation energy, given by the mass difference between the products and the reactant:

ΔE=[mnuc(Z−1,N)+mp−mnuc(Z,N)]c2\Delta E = [m_{nuc}(Z-1, N) + m_p - m_{nuc}(Z, N)] c^2

The nuclear mass mnucm_{nuc} can be expressed in terms of the atomic mass MM by subtracting the mass of the electrons:

mnuc(Z,N)=MZ,N−Zmem_{nuc}(Z, N) = M_{Z, N} - Z m_e

mnuc(Z−1,N)=MZ−1,N−(Z−1)mem_{nuc}(Z-1, N) = M_{Z-1, N} - (Z-1) m_e

Substituting these into the energy equation:

ΔE=[MZ−1,N−(Z−1)me+mp−(MZ,N−Zme)]c2\Delta E = [M_{Z-1, N} - (Z-1) m_e + m_p - (M_{Z, N} - Z m_e)] c^2

ΔE=[MZ−1,N+mp+me−MZ,N]c2\Delta E = [M_{Z-1, N} + m_p + m_e - M_{Z, N}] c^2

Since the mass of a hydrogen atom is MH=mp+meM_H = m_p + m_e (neglecting the small electronic binding energy), we get:

ΔE=(MZ−1,N+MH−MZ,N)c2\Delta E = (M_{Z-1, N} + M_H - M_{Z, N}) c^2
Practice The Nucleus on Quantrex Academy →

More from The Nucleus

A neutron star possesses a density equivalent to that of nuclear matter. Assuming the… Concepts Of Physics MCQ Edition [Volume 2]Determine the amount of energy released during the reaction given below: ^ 7 Li + p → α +… Concepts Of Physics MCQ Edition [Volume 2]Determine the binding energy per nucleon of ^ 197 _ 79 Au , given that its atomic mass is… Concepts Of Physics MCQ Edition [Volume 2]Compute the energy released if an α -particle is emitted by ^ 238 U . The atomic masses… Concepts Of Physics MCQ Edition [Volume 2]Suppose that the mass of a nucleus is roughly given by M = A m_p , where A represents the… Concepts Of Physics MCQ Edition [Volume 2]Determine the mass of an α -particle, given that its binding energy is 28.2 MeV . Concepts Of Physics MCQ Edition [Volume 2]Compute the energy that needs to be supplied to ^ 238 U in order for two protons and two… Concepts Of Physics MCQ Edition [Volume 2]Calculate the energy released in the nuclear reaction ^ 223 Ra → ^ 209 Pb + ^ 14 C . The… Concepts Of Physics MCQ Edition [Volume 2] Full The Nucleus list All Concepts Of Physics MCQ Edition [Volume 2] PYQs