The first ionization energies, in kJ mol–1 , of four elements with consecutive atomicnumbers are shown below.A 1680B 2080C 496D 738(a) Which element could be an inert gas?(1)ABCD(b) Which element could be X in a covalent compound with formula HX?(1)ABCD(c) Which element could be Y in an ionic compound with formula YH2?(1)ABCD(Total for Question 6 = 3 marks)www.dynamicpapers.com

(a) The element that could be an inert gas is B. Inert gases, or noble gases, have very high first ionization energies because they have a full valence electron shell. Therefore, they are very stable and it requires a lot of energy to remove an electron.

(b) The element that could be X in a covalent compound with formula HX is A. In a covalent compound, the elements share electrons. Therefore, the element with the highest ionization energy (which means it is the most difficult to remove an electron from) is not likely to be in a covalent compound. The element with the next highest ionization energy, A, is the most likely candidate.

(c) The element that could be Y in an ionic compound with formula YH2 is C. In an ionic compound, one element donates electrons to another. The element with the lowest ionization energy (which means it is the easiest to remove an electron from) is the most likely to be in an ionic compound. Therefore, C, with the lowest ionization energy, is the most likely candidate.