Answer:
Less than 0.033 M:
![[Z]_{eq}=2.4x10^{-3}M](https://tex.z-dn.net/?f=%5BZ%5D_%7Beq%7D%3D2.4x10%5E%7B-3%7DM)
Explanation:
Hello,
In this case, the described equilibrium is:

Thus, the law of mass action is:
![K=\frac{[Z]^2}{[A]^2[B]}=0.43](https://tex.z-dn.net/?f=K%3D%5Cfrac%7B%5BZ%5D%5E2%7D%7B%5BA%5D%5E2%5BB%5D%7D%3D0.43)
Nevertheless, given the initial concentration of Z that is 0.033 M, we should invert the equilibrium since the reaction will move leftwards:
![\frac{1}{K}=\frac{[A]^2[B]}{[Z]^2}=\frac{1}{0.43}=2.33](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7BK%7D%3D%5Cfrac%7B%5BA%5D%5E2%5BB%5D%7D%7B%5BZ%5D%5E2%7D%3D%5Cfrac%7B1%7D%7B0.43%7D%3D2.33)
Know, by introducing the change
due to the reaction extent, we can write:

Which has the following solution:

But the correct solution is
since the other solutions make the equilibrium concentration of Z negative which is not possible. In such a way, its concentration at equilibrium is:
![[Z]_{eq}=0.033M-2(0.0153M)](https://tex.z-dn.net/?f=%5BZ%5D_%7Beq%7D%3D0.033M-2%280.0153M%29)
![[Z]_{eq}=2.4x10^{-3}M](https://tex.z-dn.net/?f=%5BZ%5D_%7Beq%7D%3D2.4x10%5E%7B-3%7DM)
Which is clearly less than 0.033 M since the addition of a product shift the reaction leftwards in order to reestablish equilibrium (Le Chatelier's principle).
Regards.
Compounds are not possible to be separated by physical means
Hello!
I'm going to have to infer that you meant "grams" and not "gallons" :-)
Anyways, to find the density, you need to the divide mass over volume (d = m/V).
Since we are given the volume being 15.0 mL, and the weight being 40.5 grams, we can find the density of the aluminum block.
40.5 grams / 15.0 mL = 2.7 g/mL
Therefore, the density of the aluminum block is 2.7 grams per milliliter.
The correct answer is A. molecular formula = 2 x empirical formula
The given compound C2H10N2 is the molecular formula because the ratios of the elements are not reduced into lowest terms (empirical formula). To get the empirical formula, the ratios must be reduced to the smallest possible integral ratio which gives CH5N. As a result, the ratio between both formulas is 2.