Addition of an electron to a neutral gaseous atom alwayds leads to
(i) Formation of an anion
(ii) Liberation of energy
(iii) Decrease in proton/electron ratio

Options

A. Only (ii)
B. (i) & (ii)
C. (i) & (iii)
D. Only (i)

Answer

To solve the question regarding the addition of an electron to a neutral gaseous atom, we will analyze each of the given options step by step.

### Step 1: Understand the concept of anion formation
When an electron is added to a neutral gaseous atom, the atom gains a negative charge. This process results in the formation of an anion.

**Hint:** Remember that anions are negatively charged ions formed by the gain of electrons.

### Step 2: Analyze energy changes during electron addition
The addition of an electron to an atom can either release energy or require energy, depending on the atom's electron configuration. For most atoms, particularly those that are not noble gases, adding an electron releases energy (exothermic process). However, for noble gases (like neon or argon), adding an electron requires energy (endothermic process). Therefore, the statement about liberation of energy is not universally true.

**Hint:** Consider the electron configuration of the atom to determine if energy is released or absorbed.

### Step 3: Examine the proton/electron ratio
When an electron is added to a neutral atom, the number of electrons increases while the number of protons remains the same. This leads to a decrease in the proton-to-electron ratio.

**Hint:** Recall that the proton count does not change when electrons are added, affecting the ratio.

### Conclusion
Based on the analysis:
- (i) Formation of an anion: **True**
- (ii) Liberation of energy: **Not always true**
- (iii) Decrease in proton/electron ratio: **True**

Thus, the correct answers are (i) and (iii).

### Final Answer
The addition of an electron to a neutral gaseous atom always leads to:
- (i) Formation of an anion
- (iii) Decrease in proton/electron ratio