The steps are as followed in occurrence: (II),(III),(IV),(I)
Answer:

Explanation:
pH is derived from the concentration of hydronium ions in a solution. Hydrocyanic acid is HCN.
First, we shall figure out the moles of HCN:

If HCN was a strong acid:
HCN has a 1:1 ratio of H+ ions, the moles of H+ is also the same.
To find the molarity, we now divide by Liters. This gets us:

Finally, we plug it into the definition of pH:
![pH = -log[H^{+} ]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%7B%2B%7D%20%5D)


However, since HCN is a weak acid, it only partially dissociates. The
of HCN is
.
![K_a = \frac{[H^+][A^-]}{[HA]}](https://tex.z-dn.net/?f=K_a%20%3D%20%5Cfrac%7B%5BH%5E%2B%5D%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
We can use an ice table to determine that when x = H+,

![[H^+] = 8.83*10^{-6}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%20%3D%208.83%2A10%5E%7B-6%7D)
![pH = -log[H^{+} ]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%7B%2B%7D%20%5D)


Answer:
option d is right
Explanation:
More precipitation occurs near the equator because it is a tropical area. Mountains receive less than 15 inches of rain per year while the equator area receives a lot of rain. This is due to the very hot weather.
Well its not gravity if that helps any
Answer:
6.25 grams is the mass of solute dissolved.
Explanation:
w/w % : The percentage mass or fraction of mass of the of solute present in total mass of the solution.

Mass of the solution = 50.0 g
Mass of the solvent = x
w/w % = 12.5%

x = 6.25 g
6.25 grams is the mass of solute dissolved.