Bancrofts School1Questions on ionisation energies1.The values of the first ionisation energies of neon, sodium and magnesium are 2080, 494 and 736kJ mol1, respectively.(a)Give the definition of the term first ionisation energy of an atom.(b)Write an equation to illustrate the process occurring when the second ionisation energy of magnesium is measured.(c)Explain why the value of the first ionisation energy of magnesium is higher than that ofsodium.(d)Explain why the value of the first ionisation energy of neon is higher than that of sodium.(e) Explain why the second ionisation energy of beryllium is greater than the first ionisation energy.

2.(a)Complete the following to show the electronic configuration of silicon.1s2 2s2 ........................................................................................................................(b)Write chemical equations, including state symbols, for the following enthalpy changes:(i) the first molar ionisation energy of silicon;(ii) the second molar ionisation energy of silicon.3.The electron energy levels for atoms of an element are 1s2 2s2 2p6 3s2 3p4.a What is the atomic number of the element?b What is the name of the element?c Sketch a graph for the first seven ionisation energies of the element against thenumber of the ionisation.

Explain why the first ionisation of group 2 elements decreases down the group Explain why Helium has the biggest first ionisation energy of all the elementsWhich element would have the biggest second ionisation energy? Explain whySketch a graph for the successive ionisation energies of aluminium

The data below show the first 6 ionisation energies for three successive elements X,Y,Z in the periodic table

X20813956607893591215715244Y4964535694795521331416595Z73814477718105161360417945

Which group of the table is Y likely to be in? Explain why.What is the smallest element Z could be?Why is the first ionisation energy of X much higher than that of Y?

9. Identify the Period 2 element that has the following successive ionisation energies.

10.(i) State the general trend in first ionisation energies for the Period 2 elements lithium to nitrogen.(ii) Identify the element that deviates from this general trend, from lithium to nitrogen, and explain your answer.

11. a) State and explain the general trend in first ionisation energies for the Period 3 elements aluminium to argon.b) There is a similar general trend in first ionisation energies for the Period 4 elements gallium to krypton.State how selenium deviates from this general trend and explain your answer.c) Suggest why the first ionisation energy of krypton is lower than the first ionisation energy of argon.12. Explain why the ionisation energy of every element is endothermic.13. Predict the element in Period 3 that has the highest second ionisation energy. Give a reason for your answer.