The preparation and analysis of potassium nitrilosulfonate, N(SO3K)3.2H2O

Authors Avatar

The preparation and analysis of potassium nitrilosulfonate, N(SO3K)3.2H2O

In the synthesis of potassium nitrilosulfonate experiment a lot of techniques and apparatus were used to get the end product of potassium nitrilosulfonate crystals. Initially 10 grams of potassium metabisulfite was used to synthesize potassium nitrilosulfonate and at the end of the experiment 7.179 grams of PNS was obtained. It was found that the experiment yielded a 58.72% percentage yield and was found that it was quite near the maximum percentage yield according to previous studies. The results were written down on paper with all the necessary calculations shown.  


In the hydrolysis of PNS in acidic medium experiment about 0.5 grams of the PNS synthesised in the first experiment was weighed out and used to determine the percentage hydrolysis of PNS. The experiment was done in duplicate for more accurate results and was found that PNS hydrolysed 62.88% and 65.57% for 0.498 grams and 0.500 grams weighed out respectively. Taken the average of the two results it was found that the results showed similar percentages to previously studies. The results were tabulated on a result form.

Introduction

The aim for the first part of the experiment was to synthesise potassium nitrilosulfonate. The sulfonic acid derivatives can all be prepared from the reaction between NH3 and SO3 but in this experiment another method was followed to prepare nitrilosulfonate (figure 1& Inorganic Chemistry 244 Practical Manual, 2011:8). The K2S2O5 is prepared in situ from the hydrolysis of potassium metabisulfate. It is significant to know that no information concerning the rate of hydrolysis and stability of the primary reaction product, the nitrilosulfonate, or of the intermediate, imidodisulfonate, has been recorded thus far. The synthesis of potassium nitrilosulfonate must be done in carefully controlled conditions for the experiment to be a success (Sisler & Audrieth, 1938:1947).

Join now!

At the end of the experiment shiny, rhombic crystalline needles are formed and the pure salt can be stored in a desiccator for many weeks (Brauer, 1963:506). In acid mediums it is rapidly saponified to imidosulfonate and therefore all bisulfate must be removed with careful washing during the experiment.  Potassium nitrilosulfonate can also be saponified to amidosulfonate at boiling temperatures and therefore the temperature of the solution must be controlled at all times during the performance of the experiment (Brauer, 1963:506).

The aim of the second part of the experiment was to investigate the degree of hydrolysis of PNS ...

This is a preview of the whole essay