In this lesson, students explore a discrepant event when they design an experiment to measure the rate that ice melts when in pure water versus salt water. It is designed to help students realize that a carefully-designed experiment may yield... (View More) unexpected results, due to unseen events, even though the experiment is precisely planned and executed. The addition of a new technology may clarify factors in the experiment which were previously unknown. Note: the experiment requires advance preparation the day before: two buckets of water are set-up (one with plain tap water, the other with as much salt dissolved in it as possible), which need to be at room temperature. It also requires ice cubes of uniform shape (e.g., from an ice maker or ice trays filled to uniform capacity). This lesson is part of the Cosmic Times teachers guide and is intended to be used in conjunction with the 1993 Cosmic Times Poster. (View Less)
