Question
The first (Δ1H1) and the second (Δ1H2) ionization enthalpies (in kJ mol-1) and the (ΔegH) electron gain enthalpy (in kJ mol-1) of a few elements are given below:
| Elements | Δ1H1 | Δ1H2 | ΔegH |
| I | 520 | 7300 | -60 |
| II | 419 | 3051 | -48 |
| III | 1681 | 3374 | -328 |
| IV | 1008 | 1846 | -295 |
| V | 2372 | 5251 | +48 |
| VI | 738 | 1451 | -40 |
Which of the above elements is likely to be the metal which can form a stable binary halide of the formula MX2, (X=halogen).
Solution
Element VI has a low negative electron gain enthalpy (ΔegH). Thus, it is a metal. Further, it has the lowest second ionization enthalpy (Δ1H2). Hence, it can form a stable binary halide of the formula MX2(X=halogen).
Is there an error in this question or solution?
Solution The First (δ1h1) and the Second (δ1h2) Ionization Enthalpies (In Kj Mol-1) and the (δEgh) Electron Gain Enthalpy (In Kj Mol-1) of a Few Elements Concept: Periodic Trends and Chemical Reactivity.
