We've been learning about different materials and how they are affected by reversible and irreversible changes. First, we investigated which material could insulate an ice cube the best, so it took the longest time to melt. We worked in partnership to investigate different materials. We concluded we needed more time, as not many of the ice cubes melted at all! Next, we observed what happens when vinegar and milk are mixed, which forms casein plastic. We observed that solid lumps started to form in the liquid (and the liquid smelled really bad)! Finally, we set up a long-term experiment to see how to separate a mixture of salt and water, using evaporation. We added food dye to make the salt easier to see. After a week, we observed that some of the mixtures had separated much better than others - the purple one in particular seemed to work really well! We're going to leave this experiment going so we can observe...