In history[ edit ] Jeremias Benjamin Richter —one of the first chemists to publish tables of equivalent weights, and also the coiner of the word " stoichiometry ". The first tables of equivalent weights were published for acids and bases by Carl Friedrich Wenzel in
The question has been thoroughly answered by the other contributors.
I will only add that you should keep in mind the end use of the polymer as this will help you to decide the most promising result. Some of them are expensive. For instance, GPC provides the Mn, Mw, Mz and if the constants in the Mark-Hownik's equation for your polymer-solvent system are known, you can also get Mv, the viscosity average molecular weight.
But not many Laboratories possess GPC facilities. The other alternatives depend on which average molecular weight you are interested in.
If you want to determine the number average molecular weight and if the molecular weight is high, then Membrane Osmosis is suitable. In this method, it is advisable to go for dynamic method where you can measure the Mn upto 10,00, If you want the weight average molecular weight Mw, then light scattering method is suitable.
Using this method, you can also calculate the Radius of Gyration of the polymer which helps to know the shape of the molecule also. But for most of the biopolymer, Ultracentrifugation is the most suitable and accurate.
One can use either sedimentation velocity or sedimentation equilibrium method. But if you are interested in the determination of viscosity average molecular method Mvthen solution viscosity method using Ubbelhode viscometer is the simple and inexpensive method.
But here one must know the Mark-Hownik constants for the polymer-solvent-temperature system. But whatever is the method, if you want to determine the molecular weight accurately, the purity of your polymer is important.
It must be free from the other additives.Volumetric Analysis 3 To determine the relative molecular mass of a soluble base Introduction In Volumetric Analysis 1 & 2 you prepared a standard solution of sodium carbonate and used it to standardise an unknown concentration of dilute hydrochloric acid.
For an accurate estimation of various averages of the molecular mass, it is better to obtain the molecular mass distribution. The most reliable techniques are ultracentrifuge and light diffusion. To find the formula of washing soda Safety 1 make a solution of washing soda 2 titrate the washing soda solution against standard hydrochloric acid 3 calculate the formula of washing soda crystals (Na 2CO schwenkreis.com2O), using the titration results.
find the relative molecular mass of sodium carbonate and hence the value of x in the formula Na. Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the concentration of an identified schwenkreis.com volume measurements play a key role in titration, it is also known as volumetric analysis.A reagent, called the titrant or titrator is prepared as a standard solution.A known concentration and volume of titrant reacts.
The molecular mass calculations made using the atomic masses on the periodic table apply for general calculations, but aren't accurate when known isotopes of atoms are present in a compound.
This is because the periodic table lists values that are a weighted average of the mass of all natural isotopes of each element. Titration of Vinegar A titration involves performing a controlled reaction between a solution of known concentration (the titrant) and a solution of unknown concentration (the analyte).
series of solution stoichiometry calculations (see Calculations Section). Page 2 of 4 Procedure.