What should be done to increase the working time of alginate?

To increase the working time of alginate, the correct approach is to use water that is colder than room temperature. The setting reaction of alginate involves an interaction with calcium ions, which is accelerated by heat. When colder water is used, the reaction proceeds at a slower rate, which extends the working time for clinicians to manipulate the material before it sets.

Using water at room temperature or warmer will actually speed up the setting process and reduce the working time, as these temperatures facilitate the reaction. Distilled water can be used for mixing alginate, but it does not significantly affect the working time compared to the temperature of the water. Therefore, using cold water is the most effective method for achieving a longer working time with alginate.