Answer:
0.38
Explanation:
As you go from 0 % hexane (χ = 0) to 100 % hexane (χ = 1), the refractive index decreases from 1.407 to 1.375, a decrease of 0.032.
From 1.407 to 1.3948, the decrease is 0.0122
.
That is 0.0122/0.032 = 0.38 of the distance from χ = 0 to χ = 1.
The mole fraction of hexane is 0.38.
The diagram below is a plot of refractive index vs. the mole fraction of hexane. It shows that the refractive index drops to 1.3948 when χ = 0.38.
<span>Fred and Ethel Mertz
</span>
I believe you would weigh 30.3 pounds on the moon.
<span>Answer: 8.15s
</span><span />
<span>Explanation:
</span><span />
<span>1) A first order reaction is that whose rate is proportional to the concenration of the reactant:
</span><span />
<span>r = k [N]
</span><span />
<span>r = - d[N]/dt =
</span><span />
<span>=> -d[N]/dt = k [N]
</span><span />
<span>2) When you integrate you get:
</span><span />
<span>N - No = - kt
</span>
<span></span><span /><span>
3) Half life => N = No / 2, t = t'
</span><span />
<span>=> No - No/ 2 = kt' => No /2 = kt' => t' = (No/2) / k
</span><span />
<span>3) Plug in the data given: No = 0.884M, and k = 5.42x10⁻²M/s
</span>
<span /><span /><span>
t' = (0.884M/2) / (5.42x10⁻²M/s) = 8.15s</span>
