Question

To increase the $pH$ value of a neutral solution, we should add:
A.An acid
B.An acid salt
C.An alkali
D.A salt

Answer 1

We must remember that the more acid the solution lower the $pH$ and more basic the solution higher the $pH$.

Complete step by step answer:
Let's start this discussion with the basic question that arises in our mind which is, what actually is pH?
Well, $pH$ is nothing more than an indicator that tells us whether the substance that is with us is acidic or basic in nature. Or we can say that $pH$ is nothing more than the negative logarithm of hydrogen or ${H^ + }$ ions present in the medium. It is a scale with numbers marked from 0-14, number 7 is marked as neutral in the scale while higher than 7 is basic, and lower than 7 is acidic in nature.
So if we need to increase the $pH$ that means we need to turn the solution basic in nature.
So for this, we need to add a substance that will increase the $O{H^ - }$ ion concentration because at neutral $pH$ the balance between $O{H^ - }$ and ${H^ + }$ is equal.
For this Alkali would be the most preferred choice due to its basic nature.
When we add a base to the solution the extra $O{H^ - }$ ion will bond with ${H^ + }$ ion thus reducing the net ${H^ + }$ ion concentration of the solution and ultimately increasing the $pH$ of the solution.
Thus the correct answer for this question would be C) an alkali.

Note:
We must know that the $pH$ of a solution has very high importance in our life. The blood in our body is having a $pH$ of 7.35 to 7.45 which can be considered slightly basic. The blood acts as a buffer but in any case, the $pH$ in the blood is changed then it might cause death as some soluble content in the blood can precipitate which leads to blockage of veins. So, the $pH$ has its own importance in life.