is the scale used to describe how acidic or basic a solution is. This affects the enzymes within living systems.

pH scale

Explanation:

pH scale -

In the field of chemistry , the accurate and exact value of acidity or basicity in a particular solution is calculated with the help of a pH scale .

The scale has reading ranging from 1 to 14 ,

where ,

and ,

Hence , from the given statement of the question ,

The correct answer is pH scale .

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).