Question #55b04

2 Answers
Feb 2, 2018

Please read below;

Explanation:

The element is selenium $\left(S e\right)$

It has atomic number of $34$

Its electronic configuration is $\left[A r\right] 3 {d}^{10} 4 {s}^{2} 4 {p}^{4} \mathmr{and} 4 {s}^{2} 3 {d}^{10} 4 {s}^{2} 4 {p}^{4}$

Electron per shell is $2 , 8 , 18 , 6$

Therefore, It need to gain two electrons $\left(2 {e}^{-}\right)$ to attain the octet structure or be stable..

Feb 2, 2018

$\text{The element is located in Period 4 and in Group 16}$ $\text{and it is identified as Selenium(Se)} .$ $\text{This element will gain 2 more electrons to achieve stability.}$

Explanation:

The highest energy level is 4 which means that the element is located in $\text{Period } 4$ and that the valence electron is 6; that is, $2 {e}^{-}$ in the $s \text{ sublevel}$ and $4 {e}^{-}$ in $p \text{ sublevel}$. which means that the element is in $\text{Group } 16$

Using the periodic table, this element is identified as $\text{Selenium} \left(S e\right)$

Since the element is a nonmetal; the tendency is to gain $2 {e}^{-}$ to complete an octet and achieve stability.