In excited H atom, when electron drop from n = 4, 5, 6 to n = 1, there is emission of:

Options

A. UV light
B. Visible light
C. IR light
D. Radio waves

Explanation

To solve the question regarding the emission of light when an electron in an excited hydrogen atom drops from higher energy levels (n = 4, 5, 6) to the ground state (n = 1), we can follow these steps:

### Step 1: Understand the Energy Levels of Hydrogen
In a hydrogen atom, electrons occupy discrete energy levels denoted by the principal quantum number \( n \). The energy levels are quantized, meaning electrons can only exist in specific states.

### Step 2: Identify the Transition
The question states that the electron is dropping from higher energy levels (n = 4, 5, 6) to the lowest energy level (n = 1). This transition involves the release of energy in the form of electromagnetic radiation.

### Step 3: Determine the Series of Emission
When electrons transition to the n = 1 level, the series of spectral lines produced is known as the **Lyman series**. The Lyman series corresponds to transitions where the final energy level is n = 1.

### Step 4: Identify the Type of Emission
The energy emitted during these transitions falls within the ultraviolet (UV) region of the electromagnetic spectrum. Therefore, when electrons drop from n = 4, 5, or 6 to n = 1, they emit UV light.

### Conclusion
Thus, the emission of light when an electron drops from n = 4, 5, or 6 to n = 1 in an excited hydrogen atom results in the emission of **UV light**.

### Final Answer
The emission is **UV light** (Option A).

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