Saved Bookmarks
| 1. |
If soap has high alkal content it irritates skin. How can amount of excess alkali be determind? What can be the source of excess alkali ? |
Answer» Solution :A solution of SOAP is titrated with STANDARD HYDROCHLORIC acid. It isan acid-base titration. In this titration, PHENOLPTHALEIN is used as an indicator. During the preparation of soap, fat (i.e., glyceryl ester of fatty acid) is heated with aqueous sodium hydroxide  Thus, the source of this excess alkali (which irritates skin) is the alkali left UNUSED when the soap is preparedby hydrolyis of fat. |
|