By passing X-rays through copper sulphate crystals diffraction band is obtained. It was first observed by

Options

A. Max Van Laue
B. W.L Bragg
C. W.H. Bragg
D. W.L.Bragg & W.H.Bragg

Answer

To solve the question regarding who first observed the diffraction bands obtained by passing X-rays through copper sulfate crystals, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Experiment**: The question refers to an experiment involving X-rays and copper sulfate crystals, which leads to the observation of diffraction bands.

2. **Recall Historical Context**: The experiment in question is historically significant in the field of crystallography and X-ray diffraction. It is essential to identify the key figures involved in this discovery.

3. **Research Key Figures**: The experiment was conducted by Max von Laue, who is credited with the discovery of X-ray diffraction in crystals. He performed this experiment in 1912.

4. **Involvement of Technicians**: Max von Laue was assisted by two technicians, named Nipping and Friedrich, who helped him in the experiment. Their contributions were crucial in obtaining the diffraction patterns.

5. **Conclusion**: Based on the historical context and the individuals involved, we can conclude that the first observation of diffraction bands from X-rays passing through copper sulfate crystals was made by Max von Laue, with assistance from his technicians.

### Final Answer:
The first observation of diffraction bands obtained by passing X-rays through copper sulfate crystals was made by **Max von Laue**.

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