NCERT Solutions for Class 12 Physics Chapter 12: Atoms

Education Journalist | Study Abroad Strategy Lead

NCERT Solutions for Class 12 Physics Chapter 12 Atoms are given in this article. Atoms are the smallest unit into which matter can be divided without the release of electrically charged particles. It also is the smallest unit of matter that has the characteristic properties of a chemical element. Atom is the basic building block of chemistry.

Unit 8 Atoms and Nuclei along with Unit 7 Dual Nature of Radiation and Matter has a weightage of 12 marks in the CBSE Board examinations. The Class 12 Physics Chapter 12 NCERT Solutions cover the concepts of Atomic Spectra, Magnetic Quantum Number, and energy levels.

Download PDF: NCERT Solutions for Class 12 Physics Atoms

NCERT Solutions for Class 12 Physics Chapter 12

The NCERT solutions for Class 12 Physics Chapter 12: Atoms is given below.

NCERT Solutions

CBSE Class 12 Physics Chapter 12 – Topics Covered

Thomson’s Atomic Model: Every atom is a uniformly positive charged sphere of radius of the order of 10^-10 m, in which the entire mass is distributed uniformly and negatively charged electrons are randomly embedded randomly.

Limitations of Thomson’s Atomic Model

1. It couldn’t explain the origin of spectral series of hydrogen and other atoms.

2. It couldn’t explain the large angle scattering of α-particles.

Bohr Model of the Hydrogen Atom: An electron can revolve in certain non-radiating orbits for which the angular momentum of electron is an integer multiple of (h/2π).

\(r_n = n^2({h^2 \epsilon_o \over \pi mZe^2})\)

Hydrogen Spectrum Series: Each element emits a radiation spectrum, which is characteristic of the element itself. The spectrum is known as the line spectrum.

Hydrogen spectrum consists of 5 series – Lyman Series, Balmer Series, Paschen Series, Brackett Series, and Pfund Series.

Wave Model is based on wave mechanics. Quantum numbers are the numbers that are required to completely specify the state of the electrons.

In the presence of a strong magnetic field, the 4 quantum number are Principle quantum number, Orbital angular momentum quantum number, Magnetic quantum number, and Magnetic spin angular momentum quantum number.

Also Read:

Chapter 12 Related Articles
Structure of atom	Atomic Number	Mass Number
Subatomic Particles of Atom	Atomic Radii	Atomic Energy Level
NCERT Solution for class 12 Physics	Dalton’s Atomic Theory	Atomic Orbitals
Thomson's Atomic Model	Alpha-Particle scattering and Rutherford's Nuclear Model of Atom	Avogadro's Number
Particle Physics	Laser Light	Alpha Particle Mass

Check-Out:

PCMB Study Guides
NCERT Solutions for Class 12 Physics	Class 12 Physics Notes	Formulas in Physics
Topics for Comparison in Physics	Choice-based questions in physics	Topics in relation to physics
Physics Study Notes	Class 12 Physics Book PDF	Class 12 Physics Practicals
Important Derivations in Physics	SI units in Physics	Important Physics Constants and Units
Class 12 Physics Syllabus	Mendeleev's Periodic Table	NCERT Solutions for Class 12 Biology
NCERT Solutions for Class 12 English	NCERT Solutions for Class 11 Chemistry	Class 12 Chemistry Practicals
Class 12 Chemistry Notes	Important Chemical Reactions	Class 12 Maths Notes
Class 12 PCMB Notes	NCERT Class 12 Biology Book	NCERT Class 12 Maths Book
NCERT Class 12 Textbooks	NCERT Solutions for Class 11 Maths	NCERT Solutions for Class 11 Physics
NCERT Solutions for Class 12 Maths	NCERT Solutions for Class 11 Biology	NCERT Solutions for Class 11 English
NCERT Class 11 Chemistry Book	NCERT Class 11 Physics Book	NCERT Class 11 Biology Book
Class 11 Notes	Important Maths Formulas	Important Chemistry Formulas
Class 11 PCMB Syllabus	Chemistry Study Notes	Biology Study Notes
Periodic Table in Chemistry	Important Chemical Reactions	Comparison topics in Chemistry
Comparison Topics in Maths	Biology MCQs	Important Named Reactions
Maths MCQs	Comparison Topics in Biology	Chemistry MCQs

CBSE CLASS XII Related Questions

1.
The magnetic field in a plane electromagnetic wave travelling in glass (\( n = 1.5 \)) is given by \[ B_y = (2 \times 10^{-7} \text{ T}) \sin(\alpha x + 1.5 \times 10^{11} t) \] where \( x \) is in metres and \( t \) is in seconds. The value of \( \alpha \) is:
- \( 0.5 \times 10^3 \, \text{m}^{-1} \)
- \( 6.0 \times 10^2 \, \text{m}^{-1} \)
- \( 7.5 \times 10^2 \, \text{m}^{-1} \)
- \( 1.5 \times 10^3 \, \text{m}^{-1} \)
View Solution
2.
The energy of an electron in an orbit in hydrogen atom is \( -3.4 \, \text{eV} \). Its angular momentum in the orbit will be:
- \( \dfrac{3h}{2\pi} \)
- \( \dfrac{2h}{\pi} \)
- \( \dfrac{h}{\pi} \)
- \( \dfrac{h}{2\pi} \)
View Solution
3.
Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))
View Solution
4.
The radius of a nucleus of mass number 125 is:
- 6.0 fm
- 30 fm
- 72 fm
- 150 fm
View Solution
5.
In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.
View Solution
6.
If Bohr’s quantization postulate (angular momentum \( = \frac{nh}{2\pi} \)) is a basic law of nature, it should be equally valid for the case of planetary motion also. Why, then, do we never speak of quantization of orbits of planets around the Sun? Explain.
View Solution

View All

Similar Physics Concepts

Atoms: Thomson's Atomic Model, Rutherford's Model and Atomic Spectra

Alpha-Particle scattering and Rutherford's Nuclear Model of Atom

Bohr Model of the Hydrogen Atom: Equation, Formula and Limitations

Laser Light: Characteristics, Types, Uses

Magnetic Quantum Number: Types of Quantum Numbers, Derivation, Examples

Particle Physics with Standard Model, Formula and Uses

Franck Hertz Experiment: Theory, Elastic & Inelastic Collision

Value of 'c': Speed of Light

Bohr Radius: Explanation, Formula, Equation, Units

Alpha Particle Mass: Definition, Value, Properties & Example

CBSE CLASS XII Previous Year Papers

Physics

Physics Preparation Guides

Electric Charges and Fields: Flux, Gauss Law & Coulomb's Law

Applications of Gauss Law: Formula & Gauss Theorem

Coulomb’s Law: Formula, Vector Form & Limitations

Electric Charge: Definition, Formula, Types and Properties

Electric Field: Definition, Formula & Electric Field Direction

Gauss Law: Formula, Gauss Theorem & Electric Flux

Dipole in a Uniform External Field: Torque, Frequency, and Time Period

Electric Dipole: Definition, Significance and Electric Dipole Moment

Electric Flux: Formula, Equation, Symbol & SI Unit

Electrostatic Potential: Definition, Formula and SI Unit

Electric Potential Due to a Point Charge: Derivation & Formula

Potential Due to an Electric Dipole: Introduction, Formula and Derivation

Equipotential Surface: Work Done, Properties & Magnitude

Van de Graaff Generator: Principle, Working, and Construction

Energy Stored in a Capacitor: Formula, Derivation and Applications

Electrostatic Potential and Capacitance: Introduction & Derivations

Electric Charges and Fields Important Questions

Kirchhoff's Laws: Kirchhoff's Current and Voltage Laws & Applications

Meter Bridge: Definition, Working Principle & Examples

Potentiometer: Working Principle, Types & Applications

Physics NCERT Solutions

Doppler Shift: Formula & Applications

Volcanoes Eruption: Definition, Formation and Causes

Alpha-Particle Scattering and Rutherford’s Nuclear Model of Atom: Explanation

Tension Formula: Explanation and Solved Examples

Pressure Formula: Partial, Osmotic & Absolute Pressure

NCERT Solutions For Class 12 Physics Chapter 1: Electric Charges and Fields

NCERT Solutions For Class 12 Physics Chapter 8: Electromagnetic Waves

NCERT Solutions For Class 12 Physics Chapter 6: Electromagnetic Induction

NCERT Solutions for Class 12 Physics Chapter 13: Nuclei

NCERT Solutions For Chapter 14: Semiconductor Electronics

You can also check

NCERT Solutions for Class 12 Physics Chapter 12: Atoms

NCERT Solutions for Class 12 Physics Chapter 12

CBSE Class 12 Physics Chapter 12 – Topics Covered

CBSE CLASS XII Related Questions

1.
The magnetic field in a plane electromagnetic wave travelling in glass (\( n = 1.5 \)) is given by \[ B_y = (2 \times 10^{-7} \text{ T}) \sin(\alpha x + 1.5 \times 10^{11} t) \] where \( x \) is in metres and \( t \) is in seconds. The value of \( \alpha \) is:

2.
The energy of an electron in an orbit in hydrogen atom is \( -3.4 \, \text{eV} \). Its angular momentum in the orbit will be:

3.
Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

4.
The radius of a nucleus of mass number 125 is:

5.
In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.

6.
If Bohr’s quantization postulate (angular momentum \( = \frac{nh}{2\pi} \)) is a basic law of nature, it should be equally valid for the case of planetary motion also. Why, then, do we never speak of quantization of orbits of planets around the Sun? Explain.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

NCERT Solutions for Class 12 Physics Chapter 12: Atoms

NCERT Solutions for Class 12 Physics Chapter 12

CBSE Class 12 Physics Chapter 12 – Topics Covered

CBSE CLASS XII Related Questions

1.The magnetic field in a plane electromagnetic wave travelling in glass (\( n = 1.5 \)) is given by \[ B_y = (2 \times 10^{-7} \text{ T}) \sin(\alpha x + 1.5 \times 10^{11} t) \] where \( x \) is in metres and \( t \) is in seconds. The value of \( \alpha \) is:

2.The energy of an electron in an orbit in hydrogen atom is \( -3.4 \, \text{eV} \). Its angular momentum in the orbit will be:

3.Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

4.The radius of a nucleus of mass number 125 is:

5.In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.

6. If Bohr’s quantization postulate (angular momentum \( = \frac{nh}{2\pi} \)) is a basic law of nature, it should be equally valid for the case of planetary motion also. Why, then, do we never speak of quantization of orbits of planets around the Sun? Explain.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
The magnetic field in a plane electromagnetic wave travelling in glass (\( n = 1.5 \)) is given by \[ B_y = (2 \times 10^{-7} \text{ T}) \sin(\alpha x + 1.5 \times 10^{11} t) \] where \( x \) is in metres and \( t \) is in seconds. The value of \( \alpha \) is:

2.
The energy of an electron in an orbit in hydrogen atom is \( -3.4 \, \text{eV} \). Its angular momentum in the orbit will be:

3.
Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

4.
The radius of a nucleus of mass number 125 is:

5.
In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference pattern. Prove that the resultant intensities at maxima and minima are 4I and zero respectively.

6.
If Bohr’s quantization postulate (angular momentum \( = \frac{nh}{2\pi} \)) is a basic law of nature, it should be equally valid for the case of planetary motion also. Why, then, do we never speak of quantization of orbits of planets around the Sun? Explain.