Random Movement of particles was discovered by

Options

A. Robert Brown
B. E. Goldstein
C. James Chadwick
D. Wilheln Weins

Explanation

**Step-by-Step Solution:**

1. **Understanding Random Movement of Particles**: The random movement of particles refers to the erratic and unpredictable motion of particles in a medium, which is most commonly observed in gases and liquids.

2. **Identifying the Context**: This phenomenon is particularly noted in the behavior of gaseous and liquid particles, where they can move freely and independently due to the absence of a fixed structure.

3. **Defining Brownian Motion**: The random movement of particles is often referred to as Brownian motion. This term describes the zigzag movement of particles suspended in a fluid (liquid or gas) due to collisions with the fast-moving molecules of the fluid.

4. **Historical Context**: The concept of Brownian motion was first observed by a scientist named Robert Brown in 1827. He noticed this random movement while studying pollen grains in water.

5. **Conclusion**: Therefore, the discovery of the random movement of particles is attributed to Robert Brown, and this phenomenon is known as Brownian motion.

**Final Answer**: The random movement of particles was discovered by Robert Brown.

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