Which of the following is used to study the structure of crystals ?

Options

A. U.V. rays
B. Infrared
C. X-rays
D. Microwaves

Answer

To determine which method is used to study the structure of crystals, we can follow these steps:

### Step 1: Understand the Question
The question asks for the method or technique used to study the structure of crystals.

### Step 2: Identify Common Techniques
There are several techniques used in crystallography, including:
- X-ray diffraction
- Neutron diffraction
- Electron microscopy
- Scanning tunneling microscopy

### Step 3: Focus on X-ray Diffraction
Among these techniques, X-ray diffraction is the most widely used method. It involves directing X-rays at a crystal and analyzing the angles and intensities of the rays that are scattered by the crystal. This technique helps in determining the arrangement of atoms within the crystal structure.

### Step 4: Explain the Mechanism
When X-rays hit a crystal, they are scattered in various directions. By measuring the angles and intensities of these scattered rays, scientists can create a three-dimensional picture of the electron density within the crystal, which reveals the positions of the atoms.

### Step 5: Conclusion
Based on the above analysis, the correct answer to the question is that X-rays are used to study the structure of crystals.

### Final Answer
The correct option is X-ray (option c).

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