Answer:
- Krypton.
- Silicon.
Explanation:
Hello.
In this case, since the first element's last term in the electron configuration is 4p⁶, by looking at the fourth period, the only element having sic 4p electrons is Kr as its electron configuration is:
[tex]Kr^{36}:1s^2,2s^2,2p^6,3s^2,3p^6,4s^2,3d^1^0,4p^6[/tex]
In the second case, the element of the third period having two 3p electrons or [tex]3p^2[/tex] the last term in its electron configuration is silicon as shown below:
[tex]Si^{14}:1s^2,2s^2,2p^6,3s^2,3p^2[/tex]
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