Why should a primary standard have a high formula weight?
- Mike ALv 72 months ago
I assume this is connected with volumetric analysis. Lets say you want to make up 1 litre of a 0.1 (+/- 0.0001) M solution of your primary standard. If the substance has a low molecular mass you will be weighing out a very small amount of material and will not have sufficient accuracy for the solution to be used as a primary standard. Equally you would not want the molar mass to be too large or you could exceed the materials solubility.
You seem to have asked a few related questions so I'd suggest that you read up on volumetric analysis here:
You'll find all your answers there.