A mixture that forms when one substance dissolves another.

A molecule that has electrically charged areas.

A substance that dissolves another substance.

The amount of heat needed to increase the temperature of a certain mass of a substance by 1°C.

The combined force of attraction among water molecules and with the molecules of surrounding materials. A combination of adhesion and cohesion.

The continuous process by which water moves from Earth's surface to the atmosphere and back.

The process by which a gas changes to a liquid.

The process by which molecules at the surface of a liquid absorb enough energy to change to the gaseous state.

The process by which plants give off water vapor through their leaves.

The process by which plants use water, along with carbon dioxide and energy from the sun, to make their own food.

The tightness across the surface of water that is caused by the polar molecules pulling on one another.

Water that falls to Earth as rain, snow, hail, or sleet.

Water that fills the cracks and spaces in underground soil and rock layers.

The top of the saturated zone, or depth to the groundwater under Earth's surface.

The process by which nutrients in a lake build up over time and cause an increase in the growth of algae.

The layer of rocks and soil above the water table in which the pores contain air as well as water.

The land area that supplies water to a river system.

The area of permeable rock or soil in which the cracks and pores are totally filled with water.

An underground layer of rock or sediment that holds water.

A well in which water rises because of pressure within the aquifer.

A substance such as nitrogen or phosphorus that enables plants and algae to grow.

A stream or smaller river that feeds into a main river.

A ridge of land that separates one watershed from another.

A land area that is covered with a shallow layer of water during some or all of the year.

A lake that stores water for human use.

A characteristic of materials, such as sand and gravel, through which water easily passes.

A characteristic of materials, such as clay and granite, through which water does not easily pass.

Water is attracted to water.

Water is attracted to other substances