The first six successive ionisation energies of an unknown period 3 element M are 1012, 1900, 2910, 4960, 6270 and 21267 ~kJ/mol , respectively. Predict the formula and the chemical nature of the highest oxide of this element.

Step-by-step solution

Let us analyze the successive ionisation energies to find the maximum jump: IE ₂ / IE ₁ = 1900 / 1012 1.88 IE ₃ / IE ₂ = 2910 / 1900 1.53 IE ₄ / IE ₃ = 4960 / 2910 1.70 IE ₅ / IE ₄ = 6270 / 4960 1.26 IE ₆ / IE ₅ = 21267 / 6270 3.39 The largest jump occurs between the 5th and 6th ionisation energies. This indicates that the element has 5 valence electrons, as the 6th electron is removed from a stable noble gas core. An element with 5 valence electrons belongs to Group 15. Since it is a period 3 element, it is Phosph