Christopher and kate noticed that after a rainstorm some of the rocks in their yard appear to shrink. they wondered how the mass of the rocks changed when dissolved in water. to determine this, kate purchased a variety of rocks from a local shop, carefully recording the types of rocks in a data chart. christopher gathered rocks from the backyard to add to the rocks kate purchased. they measured each rock's initial mass; then they inserted the rocks one by one into 100 milliliters of water and measured the mass of each rock after it had sat in the water for five minutes. both christopher and kate concluded that store-bought rocks do not dissolve in water. they also concluded that to get rocks that dissolve in water they must be gathered directly from the yard.