Answer:
Yes. Example: <u>Sulfur hexafluoride (SF₆) molecule</u>
Explanation:
According to the octet rule, elements tend to form chemical bonds in order to have <u>8 electrons in their valence shell</u> and gain the stable s²p⁶ electronic configuration.
However, this rule is generally followed by main group elements only.
Exception: <u>SF₆ molecule</u>
In this molecule, six fluorine atoms are attached to the central sulfur atom by single covalent bonds.
<u>Each fluorine atom has 8 electrons in their valence shells</u>. Thus, it <u>follows the octet rule.</u>
Whereas, there are <u>12 electrons around the central sulfur atom</u> in the SF₆ molecule. Therefore, <u>sulfur does not follow the octet rule.</u>
<u>Therefore, the SF₆ molecule is known as a </u><u>hypervalent molecule</u><u> or expanded-valence molecule.</u>
Answer: Concentration of
in the equilibrium mixture is 0.31 M
Explanation:
Equilibrium concentration of
= 0.729 M
The given balanced equilibrium reaction is,
![2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)](https://tex.z-dn.net/?f=2NH_3%28g%29%5Crightleftharpoons%20N_2%28g%29%2B3H_2%28g%29)
Initial conc. x 0 0
At eqm. conc. (x-2y) M (y) M (3y) M
The expression for equilibrium constant for this reaction will be:
3y = 0.729 M
y = 0.243 M
![K_c=\frac{[y]\times [3y]^3}{[x-2y]^2}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5By%5D%5Ctimes%20%5B3y%5D%5E3%7D%7B%5Bx-2y%5D%5E2%7D)
Now put all the given values in this expression, we get :
![K_c=\frac{0.243\times (0.729)^3}{(x-2\times 0.243)^2}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B0.243%5Ctimes%20%280.729%29%5E3%7D%7B%28x-2%5Ctimes%200.243%29%5E2%7D)
![0.967=\frac{0.243\times (0.729)^3}{(x-2\times 0.243)^2}](https://tex.z-dn.net/?f=0.967%3D%5Cfrac%7B0.243%5Ctimes%20%280.729%29%5E3%7D%7B%28x-2%5Ctimes%200.243%29%5E2%7D)
![x=0.80](https://tex.z-dn.net/?f=x%3D0.80)
concentration of
in the equilibrium mixture = ![0.80-2\times 0.243=0.31](https://tex.z-dn.net/?f=0.80-2%5Ctimes%200.243%3D0.31)
Thus concentration of
in the equilibrium mixture is 0.31 M
Answer:
A is the answer as long as i can remember i was taught