Created by StemPy LabThe first five ionisation enthalpies of an element X, which lies in period 3, are: , , , , . X forms an oxide in which it shows its group oxidation state. Which statement about the formula and the acid-base behaviour of this oxide is correct?
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← The first ionisation enthalpies of the eight elements of one short period are listed in order of increasing atomic number, using the letters A to H. The values in kJ mol⁻¹ are: A 496, B 738, C 577, D 786, E 1000, F 1012, G 1251, H 1521. When the table was copied, the values of exactly one pair of elements were interchanged. Every other value is correct. Which statement fits the data?Data: for oxygen, the first electron gain enthalpy is -141 kJ mol⁻¹ and the second is +780 kJ mol⁻¹. Consider four statements. S1: ΔegH of Cl is more negative than that of F, because an electron added to the compact 2p subshell of F meets strong repulsion. S2: Be and N have positive or near-zero ΔegH for the same reason: the added electron enters a new, higher-energy subshell. S3: for O(g) + 2e⁻ → O²⁻(g), Δ H = +639 kJ mol⁻¹. S4: because of S1, Cl₂ is a stronger oxidising agent than F₂ in water. Which statements are correct? →
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