The amount of energy which is released due to addition of ectra electron to the outermost orbit of gaseous atom is called

Options

A. ionization enthalpy
B. Hydration enthalpy
C. Electronegativity
D. electron gain enthalpy

Answer

To solve the question regarding the amount of energy released when an extra electron is added to the outermost orbit of a gaseous atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept**:
- The question asks about the energy change that occurs when an electron is added to a gaseous atom. This process involves energy dynamics that can be quantified.

2. **Defining the Term**:
- The specific term used to describe the energy released during this process is known as "electron gain enthalpy."

3. **Chemical Representation**:
- When an electron is added to a neutral atom (let's denote it as atom X), it transforms into a negatively charged ion (X⁻). The reaction can be represented as:
\[ X(g) + e^- \rightarrow X^-(g) \]
- Here, \(X(g)\) represents the gaseous atom, and \(e^-\) is the added electron.

4. **Energy Change**:
- The energy change associated with this process is termed as electron gain enthalpy (ΔEGH). It is defined as the amount of energy released when an electron is added to a neutral gaseous atom.

5. **Sign of the Enthalpy**:
- Since energy is released during this process, the value of ΔEGH is negative. This indicates that the system loses energy when the electron is added.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the amount of energy released due to the addition of an extra electron to the outermost orbit of a gaseous atom is called "electron gain enthalpy."

### Final Answer:
The amount of energy released due to the addition of an extra electron to the outermost orbit of a gaseous atom is called **electron gain enthalpy**.

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