Chapter 11, Problem 11.50P

Interpretation Introduction

Interpretation:

The importance of choosing a compound of high equivalent mass to use as primary standard has to be explained.

Concept introduction:

Primary standard is a chemical substance used as a reference to determine the unknown concentration of a substance in a solution or any mixture.  When we weigh certain quantity of primary standard the weight of it correlates to the actual number of moles of the substance.  Primary standard is supposed to agree with the following criteria –

• Must be available with high purity
• Must be stable under the conditions of proper storage.
• It should have higher molecular weight so as to minimize the effects caused by errors in weighing.