I think 400 force is required, although i am not that sure. Hope this helps!
Your answer is: Kc = [HI]² / {[H2] [I2]}
<span>53.3 = (2x)² / {(0.400M - x)(0.400M - x)} </span>
<span>sqrt(53.3) = 2x / (0.400M - x) </span>
<span>2.92 - 7.30x = 2x </span>
<span>x = 0.314M </span>
<span>[HI] = 2x = 0.628M
:) hopefully this helped. (:</span>
Answer:
8.0 s.
Explanation:
Hello,
In this, case, by knowing that the half-life time allows as to compute the rate constant in terms of the initial concentration as shown below:
![k=\frac{1}{[NO]_0*t_{/2}} = \frac{1}{[NO]_0*2.0}=\frac{1}{2[NO]_0}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B1%7D%7B%5BNO%5D_0%2At_%7B%2F2%7D%7D%20%3D%20%5Cfrac%7B1%7D%7B%5BNO%5D_0%2A2.0%7D%3D%5Cfrac%7B1%7D%7B2%5BNO%5D_0%7D)
Therefore, the fourth half-life time implies that the concentration is 1/16 the initial one, therefore:

That is analyzed considering that if the initial concentration is 1M the first half-time is at 0.5M, the second at 0.25M, the third at 0.125M and the fourth at 0.0625M which is 16 times smaller than 1M.
Best regards.
The answer would be C.
The salt and the water have both undergone physical changes.
Hope this helps!