Question

The concept that provided a convincing evidence of the atomic picture of matter is

• A. Photoelectric effect
• B. Brownian motion theory
• C. Superconductivity
• D. Wave nature of electrons

Hint:

\[ \boxed{ \text{Brownian motion} \longrightarrow \text{Experimental evidence for the atomic nature of matter} } \]

Answer 1

The Correct Option is B

Step 1: Recall the significance of Brownian motion. Brownian motion is the random zig-zag motion of microscopic particles suspended in a fluid. This motion is caused by continuous collisions with the molecules of the surrounding medium, providing convincing evidence for the \[ \boxed{\text{Atomic (molecular) nature of matter}.} \]

Step 2: Eliminate the remaining options. \[ \begin{aligned} \text{Photoelectric effect} &\rightarrow \text{Evidence for particle nature of light} \text{Superconductivity} &\rightarrow \text{Zero electrical resistance at low temperature} \text{Wave nature of electrons} &\rightarrow \text{de Broglie hypothesis} \end{aligned} \]

Step 3: Choose the correct option. Hence, \[ \boxed{(B)} \] is the correct answer.