In H atom when electron jumps from 1s to 2s orbital,

Options

A. energy is released
B. energy and absorbed
C. the atom becomes cation
D. size of the atom decreases

Explanation

To solve the question regarding the behavior of an electron in a hydrogen atom when it jumps from the 1s to the 2s orbital, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Orbitals**:
- The hydrogen atom has different energy levels represented by orbitals. The 1s orbital is the closest to the nucleus and has the lowest energy. The 2s orbital is further away and has a higher energy level.

2. **Ground State vs. Excited State**:
- In the ground state, the electron occupies the lowest available energy level, which is the 1s orbital. When the electron moves to a higher energy level (the 2s orbital), it is said to be in an excited state.

3. **Energy Absorption**:
- For an electron to move from a lower energy level (1s) to a higher energy level (2s), it must absorb energy. This energy can come from various sources, such as light or heat.

4. **Conclusion on Energy Change**:
- Since the electron is moving from the 1s to the 2s orbital, energy is absorbed during this transition. Therefore, the correct answer to the question is that energy is absorbed.

5. **Other Options Analysis**:
- The atom does not become a cation because a cation is formed when an electron is removed from the atom, not when it is excited to a higher energy level.
- The size of the atom does not decrease in this process; rather, the electron is moving to a higher energy level, which typically means it is further from the nucleus.

### Final Answer:
- **Energy is absorbed** when the electron jumps from the 1s to the 2s orbital in a hydrogen atom.

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