The energy liberated when an excited electron returns to its ground state can have:

Options

A. Any value from zero to infinity
B. Only specified negative values
C. Only specified positive values
D. Only a value of zero

Explanation

To solve the question regarding the energy liberated when an excited electron returns to its ground state, we can follow these steps:

### Step 1: Understand the Concept of Energy States
Electrons in an atom can exist in different energy states. The ground state is the lowest energy state, while the excited state is a higher energy state. When an electron absorbs energy, it can move from the ground state to an excited state.

**Hint:** Remember that energy levels in an atom are quantized, meaning they have specific values.

### Step 2: Transition from Excited State to Ground State
When an electron in an excited state returns to the ground state, it releases energy. This energy can be emitted in various forms, such as light (photons) or heat.

**Hint:** Think about the conservation of energy principle: the energy absorbed to reach the excited state is released when returning to the ground state.

### Step 3: Determine the Nature of the Energy Released
The energy released when the electron transitions back to the ground state is a positive quantity. This is because the electron is moving to a lower energy level, and energy is released in the process.

**Hint:** Consider that energy released is often described as positive because it is the energy that is given off.

### Step 4: Evaluate the Possible Options
Now, let's evaluate the options given in the question:
- **0 to infinity:** This suggests a range of values, which is incorrect because the energy released is not infinite.
- **Only negative values:** This is incorrect as energy cannot be negative when released in this context.
- **Only positive values:** This is correct since the energy released is a specific positive value.
- **Only a value of 0:** This is incorrect since there is energy released when moving from excited to ground state.

**Hint:** Eliminate options that do not align with the concept of energy transitions.

### Step 5: Conclusion
The correct answer is that the energy liberated when an excited electron returns to its ground state can only have specified positive values.

**Final Answer:** The energy liberated when an excited electron returns to its ground state can have only specified positive values.

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