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Assertion (A) : Hydrogen has only one el...

Assertion (A) : Hydrogen has only one electron in its 1s orbital but it produces several spectral lines.
Reason (R) : There are many excited energy levels available in H atoms.

A

Both A and R true and R is the correct explanation of A

B

Both A and R are true but R is not a correct explanation of A

C

A is true but R is false

D

A is false but R is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion (A)**: - The assertion states that hydrogen has only one electron in its 1s orbital but produces several spectral lines. - Hydrogen's electron configuration is indeed 1s¹, meaning it has one electron in the first energy level (1s orbital). 2. **Understanding the Reason (R)**: - The reason states that there are many excited energy levels available in hydrogen atoms. - Hydrogen has multiple energy levels (n = 1, 2, 3, 4, etc.), and when the single electron in hydrogen absorbs energy, it can be excited to these higher energy levels. 3. **Linking Assertion and Reason**: - When the electron in hydrogen is excited to a higher energy level and then returns to a lower energy level (ground state), it emits energy in the form of light. - This emitted light corresponds to specific wavelengths, which result in the spectral lines observed in hydrogen's emission spectrum. 4. **Conclusion**: - Both the assertion and reason are true. The reason correctly explains why the assertion is true: the presence of multiple excited energy levels allows the single electron in hydrogen to produce several spectral lines upon returning to lower energy states. 5. **Final Answer**: - Therefore, the correct conclusion is that both the assertion and reason are true, and the reason is the correct explanation for the assertion.
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