Classification of Elements and Periodicity in Properties Set-3

Q1. Electron Gain Enthalpy ($\Delta_{eg} H$) is defined as the enthalpy change accompanying the process where a neutral gaseous atom ($\text{X}$) forms:

Q2. Group 17 elements (Halogens) have highly negative electron gain enthalpies because:

Q3. Why do Noble Gases have large positive electron gain enthalpies?

Q4. Among $\text{P, S, Cl, F}$, which element will have the most negative electron gain enthalpy ($\Delta_{eg} H$)?

Q5. Why is the electron gain enthalpy of Oxygen ($\text{O}$) less negative than that of Sulfur ($\text{S}$)?

Q6. What is the fundamental difference between Electron Gain Enthalpy and Electronegativity?

Q7. Electronegativity generally increases across a period because:

Q8. Which scale, used to quantify electronegativity, arbitrarily assigned a value of $4.0$ to Fluorine?

Q9. Which of the following sets of elements exhibits the strongest tendency to form an anion (i.e., highest non-metallic character)?

Q10. The second electron gain enthalpy of Oxygen ($\text{O}^{-} \to \text{O}^{2-}$):