[vanklik]

Hi everyone! I'm new to this forum and really hope to get some help.

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The first 6 ionisation energies in KJ/mole for an element X are: 596, 1152, 4918, 6480, 8150, 18378.
Explain the pattern in the values and deduce which group of the periodic table element X is in.
***

I know that the element X is in group 2 as the first two electrons are easy to remove and I think it's calcium but I can not work out why there is such increase in the 6th ionisation energy of the element X.

Could anyone help to explain that, please? 

[yukiheart]

I think the same to you.... It 's in Group II.

[renge ishyo]

Yes, it's probably calcium in group II. If that is the case the 6th Ionization energy would indeed be a typo. Compare your question data with the actual ionization energies of calcium on webelements:

http://www.webelements.com/calcium/atoms.html

[vanklik]

Thanks for the link. I've compared the question data with the IE of calcium on the website and most of them almost equal apart from the 6th one. I will have to talk to my teacher.
Thanks again!