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Given below are the first five successive ionization energies $(\mathrm{IE})$ in $\pu{kJ mol-1}$ of an element in period 3.

$$ \begin{array}{ccccc} \hline \mathrm{IE_1} & \mathrm{IE_2} & \mathrm{IE_3} & \mathrm{IE_4} & \mathrm{IE_5} \\ \hline 801 & 2427 & 3659 & 25022 & 32822 \\ \hline \end{array} $$

Deduce the electronic configuration of the valence energy level of the element. Explain how you came to this answer.

I need clarification on this question. I have explained into using my own knowledge, therefore correct me if am wrong.

I believe that the element in period three would be Al, since there is a big jump from $\pu{3659 kJ/mol}$ to $\pu{25022 kJ/mol}$. For the first three electron $\mathrm{(3s)^2(3p)^1}$, they are all in the same energy level which is the third shell and that takes $\pu{801 kJ/mol} + \pu{2427 kJ/mol} + \pu{3659 kJ/mol}$ to remove them, after that we notice a big jump after the third ionization energy indicating the its entering a new level of energy which is the second energy level.

Please advice me if its correct or not.

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Yes, your reasoning is logical and makes sense, but the question must have a typo because those IE values are the exact match for boron B, an element from period 2 right above aluminium Al (data from [1, p. 10-204], converted from $\pu{eV}$ to $\pu{kJ mol-1}$):

\begin{array}{lccccc} \hline \text{Element} & \mathrm{IE_1} & \mathrm{IE_2} & \mathrm{IE_3} & \mathrm{IE_4} & \mathrm{IE_5} \\ \hline \ce{B} & 801 & 2427 & 3659 & 25022 & 32822 \\ \ce{Al} & 578 & 1816 & 2745 & 11580 & 14842 \\ \ce{Ga} & 580 & 1980 & 2965 & 6102 & 8299 \\ \ce{In} & 559 & 1821 & 2704 & 5210 & \\ \ce{Tl} & 589 & 1971 & 2878 & & \\ \hline \end{array}

enter image description here

Another hint that it's not aluminium is the absolute value of the jump in energy between $\mathrm{IE_3}$ and $\mathrm{IE_4}$, which is too high for latter group 13 elements. Probably the author meant group 13, not period 3, but that's just a speculation at this point.

References

  1. Haynes, W. M.; Lide, D. R.; Bruno, T. J. CRC Handbook of Chemistry and Physics: A Ready-Reference Book of Chemical and Physical Data.; 2017; Vol. 97. ISBN 978-1-4987-5429-3.

Appendix

Source code for the plot, pgfplots:

\documentclass{standalone}
\usepackage{pgfplots}
\usepackage{siunitx}

\begin{document}

\begin{tikzpicture}
    \begin{axis}[
        title={Successive ionization energies of group 13 elements},
        xmin=1, xmax=5,
        ymin=0, ymax=35000,
        xlabel = $i$,
        ylabel = {$\mathrm{IE}_i$/\si{\kilo\joule\per\mole}},
        minor tick num = 1,
        mark = *,
        grid,
        legend cell align = {left},
        legend pos = north west,
    ]

    \addplot coordinates {
        (1,801)
        (2,2427)
        (3,3659)
        (4,25022)
        (5,32822)
    };
    \addlegendentry{Boron}

    \addplot coordinates {
        (1,578)
        (2,1816)
        (3,2745)
        (4,11580)
        (5,14842)
    };
    \addlegendentry{Aluminium}

    \addplot coordinates {
        (1,580)
        (2,1980)
        (3,2965)
        (4,6102)
        (5,8299)
    };
    \addlegendentry{Gallium}

    \addplot coordinates {
        (1,559)
        (2,1821)
        (3,2704)
        (4,5210)
    };
    \addlegendentry{Indium}

    \addplot coordinates {
        (1,589)
        (2,1971)
        (3,2878)
    };
    \addlegendentry{Thallium}

    \end{axis}
\end{tikzpicture}

\end{document}

Converted to PNG with the following command:

magick convert -density 120 G13_ionization_energies.pdf -quality 100 G13_ionization_energies.png

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  • $\begingroup$ thank you, so much i will have to confront my teacher about this. Again thank you $\endgroup$ – Georgy Mar 12 at 3:25
  • $\begingroup$ @Georgy No prob, just don't be harsh with your teacher: it shouldn't be a confrontation, rather a discussion supplied by your argumentation. We are people and make mistakes sometimes. $\endgroup$ – andselisk Mar 12 at 12:03

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