Water Chemistry

• Adhesion - refers to the tendency of some substances to cling to other substances.
• "ad” for “other” and “hesion” for “to stick to.”
• Adhesion - Adhesion is usually caused by interactions between the molecules of the two substances.
• Capillary Action - a reaction that results from adhesion that enables water to “climb” upwards through thin glass tubes
• Cohesion - a measure of how well molecules stick to each other or group together. It is caused by the cohesive attractive force between like molecules.
• Condensation - the process by which water vapor in the air is changed into liquid water.
• Desalination - the process of removing excess salt and minerals from water in order to produce fresh or potable water that is suitable for both humans and animals to consume and for irrigation.
• Diffusion - the tendency of substances to move from areas of high concentration to areas of low concentration
• Dissolved Oxygen - the amount of gaseous oxygen (O2) dissolved in the water.
• Epilimnion - the upper layer of water in a stratified lake.
• Eutrophication - excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.
• Evaporation - the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor.
• Evapotranspiration - the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants.
• Hydrosphere - the combined mass of water found on, under, and above the surface of a planet, minor planet or natural satellite.
• Hypolimnion - the lower layer of water in a stratified lake, typically cooler than the water above and relatively stagnant.
• Osmosis - the net movement of water across a selectively permeable membrane driven by a difference in solute concentrations on the two sides of the membrane
• pH - a scale used to specify how acidic or basic (or alkaline) a water-based solution is.
• Precipitation - water released from clouds in the form of rain, freezing rain, sleet, snow, or hail.
• Runoff - the draining away of water (or substances carried in it) from the surface of an area
• Salinity - the saltiness or amount of salt dissolved in a body of water.
• Surface Tension - a physical property equal to the amount of force per unit area necessary to expand the surface of a liquid.
• Thermal Stratification - when an appreciable temperature difference exists between the two layers, they do not mix, but behave independently and have very different chemical and biological properties
• Thermocline - a steep temperature gradient in a body of water such as a lake, marked by a layer above and below which the water is at different temperatures.
• Transpiration - the process in which some water within plants evaporates into the atmosphere
• 72.8% of it is saltwater
• 21.2% is the freshwater.
• About 60-70% of our body is made up of water
• Water is made up of two atoms of hydrogen and one atom of Oxygen.
• Properties of Water: Polarity, Hydrogen Bonding, Cohesion, Adhesion, Density, Heat Capacity, Evaporative Cooling, Universal Solvent, Acids and Bases, pH scale
• Water cycle, also called hydrologic cycle - cycle that involves the continuous circulation of water in the Earth-atmosphere system.
• Processes of water cycle - evaporation, transpiration, condensation, precipitation, and runoff.
• Evaporation - is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor.
• Condensation - is the process by which water vapor in the air is changed into liquid water.
• Condensation - is crucial to the water cycle because it is responsible for the formation of clouds.
• Precipitation - is water released from clouds in the form of rain, freezing rain, sleet, snow, or hail.
• Types of Water - Ocean, Ice/Icebergs, Rivers and Lakes, Groundwater
• Ocean - is a continuous body of saltwater that covers more than 70 percent of the Earth's surface.
• iceberg or ice mountain - is a large piece of freshwater ice that has broken off a glacier or an ice shelf and is floating freely in open water.
• river - is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river.
• Groundwater - is the water found underground in the cracks and spaces in soil, sand and rock.