Answer:
Following are the responses to the given choices:
Explanation:
For point a:
Using the acid and base which are strong so,
moles of
(from
)
moles of
(from
)
So,
i.e.
mol of
in excess in total volume
i.e. concentration of
![p[OH^{-}] = -\log [OH^{-}] = -\log [2 \times 10^{-4}\ mol] = 3.70](https://tex.z-dn.net/?f=p%5BOH%5E%7B-%7D%5D%20%3D%20-%5Clog%20%5BOH%5E%7B-%7D%5D%20%3D%20-%5Clog%20%5B2%20%5Ctimes%2010%5E%7B-4%7D%5C%20mol%5D%20%3D%203.70)
Since, 
so,
For point b:
moles of
= from point a
moles of
(from
):

1 mol
neutralizes 1 mol of
So,
i.e.
in excess in the total volume of
i.e. concentration of
Hence, ![pH = -\log [H^+] = -\log[2 \times 10^{-4}] = 3.70](https://tex.z-dn.net/?f=pH%20%3D%20-%5Clog%20%5BH%5E%2B%5D%20%3D%20-%5Clog%5B2%20%5Ctimes%2010%5E%7B-4%7D%5D%20%3D%203.70)
The glass containing the effervescence tablet has a greater air space than the other.
<h3>What is effervescence?</h3>
The term effervescence refers to the evolution of a gas. An effervescence tablet is a tablet that is designed to release the gas called carbon dioxide.
When we add the effervescence tablet and compare the level of the water in the two bowls, we will see that the water in the glass containing the effervescence tablet has a greater air space than the other.
Learn more about carbon dioxide:brainly.com/question/14445045
There are 30 protons and 39 neutrons in the nucleus.
This must me the isotope of an element with an atomic mass close to 69 u.
The only candidates are Zn and Ga.
Zn has a zinc-69 isotope with mass 68.926 u.
Ga has a gallium -69 isotope with mass 68.925 u.
The isotope is probably

.
It has 30 protons and 39 neutrons.