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Postby reva_bajjuri » Sun Nov 08, 2020 3:18 pm

Is selenium also an exception to the octet rule? I remember learning this in high school chemistry but didnt see it mentioned anywhere in the lectures or textbook.

Neha Gupta 2A
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Re: selenium

Postby Neha Gupta 2A » Sun Nov 08, 2020 3:55 pm

I think it is since it's in the fourth row, so it has access to the 3d orbital, which gives it an expanded octet.

Linette Choi 3L
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Re: selenium

Postby Linette Choi 3L » Sun Nov 08, 2020 4:01 pm

I believe selenium can have an expanded octet due to the fact that it is in the same group as Sulfur and follows the same pattern of expanded octets and bonding pairs.

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Re: selenium

Postby Brian_Wu_3B » Sun Nov 08, 2020 4:07 pm

Selenium is in the same group as sulfur which in lecture was an example of an expanded octet (SO4^2-)

Khoa Vu 3l
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Re: selenium

Postby Khoa Vu 3l » Sun Nov 08, 2020 4:07 pm

I believe that any element from the third period and beyond (n=3) can make use of the expanded octet because of their access to the same principal energy level d-orbital, which allows for an expanded octet. Selenium, which is located in the period and is n=4, should have access to the empty 4d orbital, which is on the same principal energy level, and utilize it to form an expanded octet. This is the case for elements like Phosphorous (n=3) in PCl5, which utilizes the empty 3d orbitals to fulfill its expanded octet.

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Re: selenium

Postby joshtully » Sun Nov 08, 2020 11:42 pm

Yes, selenium is an exception to the octet rule.

Edward Castro
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Re: selenium

Postby Edward Castro » Sun Nov 08, 2020 11:45 pm

Yes Selenium corresponds towards the octet rule

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