A. and D. would be the best pick for this sort of experiment, but maybe (unlikely) B. because you could see how they could react in certain situations, how they react to danger but I suggest A.
Hope this helps you ☁︎☀︎☁︎
Hihihihihihihihihihihihihi
Hibiscus I
Hi yes
Explanation:
The reaction equation will be as follows.

Hence, the expression for
is as follows.
![K_{a} = \frac{[H_{2}SO^{-}_{4}][H^{+}]}{[H_{3}AsO_{4}]}](https://tex.z-dn.net/?f=K_%7Ba%7D%20%3D%20%5Cfrac%7B%5BH_%7B2%7DSO%5E%7B-%7D_%7B4%7D%5D%5BH%5E%7B%2B%7D%5D%7D%7B%5BH_%7B3%7DAsO_%7B4%7D%5D%7D)
Let us assume that the concentration of both
and
is x.

x = 0.01118034
This means that the concentration of
is 0.01118034.
Since, we know that the relation between pH and concentration of hydrogen ions is as follows.
pH = ![-log [H^{+}]](https://tex.z-dn.net/?f=-log%20%5BH%5E%7B%2B%7D%5D)
= 
= 1.958
Thus, we can conclude that the pH of a 0.500 M solution of arsenic acid is 1.958.
The oxidation is occurring on Calcium ions as it release one electron and reduction will be occurring on fluorine ion as it accepts one electron.
<u>Explanation:</u>
An element will undergo oxidation and form a positive ion on releasing one or more electrons from its valence shell. While reduction is occurred in a chemical reaction, then the element will be forming a negative ion with the acceptance of one or more electrons in its valence shell.
So in the given process of calcium fluoride, the one electron from the valence shell of calcium will be released making it as
ions and this is termed as oxidation process. This one electron will be getting accepted by the fluorine ion and thus it will convert to
ions. This process of acceptance of electrons is termed as reduction.