Select the correct statements (s):

Options

A. The phenomena of diffraction of light can only be explained by assuming that light behaves as waves
B. de- Broglie postulate the dual character existed with matter
C. In atomic model Bohr considered electron as a particle
D. Wave nature of electrons was proved when diffraction rings were observed photographically when a stream of protons was passed through a metal foil

Answer

To solve the question of selecting the correct statements regarding atomic structure and the nature of light and matter, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A**: "The phenomena of diffraction of light can be explained by assuming that light behaves as a wave."
- **Analysis**: Diffraction is a phenomenon that occurs when light waves encounter an obstacle or slit that is comparable in size to its wavelength. This bending of light around edges is a characteristic behavior of waves. Therefore, this statement is **correct**.

2. **Statement B**: "De Broglie postulated that the dual character existed with matter."
- **Analysis**: Louis de Broglie proposed that all matter exhibits both wave-like and particle-like properties. He introduced the concept of matter waves and provided the equation λ = h/p (where λ is the wavelength, h is Planck's constant, and p is the momentum). This statement is also **correct**.

3. **Statement C**: "In atomic model, Bohr considered the electron as a particle."
- **Analysis**: Niels Bohr's atomic model treated electrons as particles that move in defined orbits around the nucleus. He calculated the velocities of these electrons and introduced the concept of quantized energy levels. This statement is **correct**.

4. **Statement D**: "Wave nature of electrons was proved when diffraction rings were observed photographically when a stream of protons was passed through a metal."
- **Analysis**: The wave nature of electrons was demonstrated in the Davisson-Germer experiment, which involved a beam of electrons, not protons. The diffraction rings observed were due to electrons interacting with a crystal lattice. Therefore, this statement is **incorrect**.

### Conclusion:
The correct statements are A, B, and C. Statement D is incorrect.

### Final Answer:
- Correct Statements: A, B, C
- Incorrect Statement: D