The sodium content of carboxymethyl cellulose (CMC) can be determined by titration. Specific steps are as follows:
Take a certain amount of carboxymethyl cellulose (CMC) sample, add an appropriate amount of water to dissolve and adjust it to be acid-base neutral;
Take a certain amount of silver nitrate standard solution, add it to the sample and mix it by shaking. At this time, the sodium ion in the carboxymethyl cellulose will react with the silver nitrate to form a white precipitate;
Continue to drop potassium chloride standard solution to continue the reaction until all the precipitates are dissolved and reddish brown precipitates appear;
Record the volume V1 of the potassium chloride standard solution added dropwise, and calculate the content of sodium ions in the carboxymethyl cellulose sample.
NBCHAO reminds you: During the titration process, the titration rate and stirring intensity should be strictly controlled to ensure a complete and accurate reaction. At the same time, a relatively stable temperature and humidity should be maintained in the laboratory to avoid the external environment from interfering with the accuracy of the measurement results.
