Ashopkeeper has a few bottles of soft drinks in his shop. but, these are not labelled. he has to serve the drinks on the demand on customers. one customer wants acidic drinks; another wants basic drinks. how will he decide which drink is to be served to whom?

He will decide which drink is to be served to whom, by the use of litmus paper.

Explanation:

The litmus paper is the most common indicator to determine the acidity or basicity of a solution. Blue litmus paper changes its color to red when a solution changes from basic to acidic while red litmus paper changes its color to blue when the opposite occurs (acid → basic).

First of all the litmus paper strip, pH indicator, is immersed in a solution and allowed to pass between 10 and 15 seconds while keeping the strip submerged.  Afterwards it is removed, and then the strip compares the color. If the color is diffuse, there is a color scale where it is determined which solution has alkaline or acidic pH

where's the diagram?

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates