Chapter 1: Water Vocabulary Review Tools A B Density the amount of mass in a unit of volume; how heavy it is for its size Polar Molecule act similar to tiny magnets, attracting other molecules Surface Water Lakes, Stream, Ponds, Rivers Groundwater water that is held underground in layers of rock and sediment Irrigation Piping in water from elsewhere and using it to grow crops Cohesion the attraction among water molecules Specific Heat the amount of energy that is needed to raise the temperature of 1 kg of a substance 1 degree C Water Conservation the careful use and protection of water Soil Water part of groundwater that is held within openings in the soil aquifer layer of rock or sediment that has enough well-connected openings to allow groundwater to flow through it Fusion energy that changes water from a SOLID TO A LIQUID Vaporization energy that changes water from a LIQUID TO A GAS Universal Solvent water is called this because it dissolves more things than any other liquid