Leonard measures 20 grams of water into a bowl and puts it in the freezer a day later he takes out the freezer and observes that it is larger than before
This is because when water freezes, it expands as it turns from liquid to solid form. The molecules in water lock into a crystalline structure when it freezes, causing it to take up more space than when it was in liquid form. This is why the frozen water in the bowl appears larger than the 20 grams of liquid water that was put into the freezer.
