Difference between revisions of "Water"
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Revision as of 07:30, 17 October 2015
Water is a chemical compound with the formula H2O and is a versatile solvent often used in the laboratory.
Contents
Properties
Chemical
Water the most commonly used laboratory solvent, due to its property of not being flammable like many other solvents, ability to dissolve a wide range of compounds, cheapness and availability, and non-toxicity as well as being mostly inert.
Self-ionization
Water is able to ionize and form hydronium and hydroxide ions in solution in concentrations of about one ten millionth of a molar.
Physical
Water is a colorless liquid with a density of 1.00g/ml, a boiling point of 100°C, and a freezing point of 0°C. It is odorless, tasteless, and somewhat volatile.
Availability
Distilled water is available at most grocery stores for less than one dollar per gallon. Tap water is essentially free. Some home setups for distillation of water can actually produce enough distilled water for lab use, but energy costs are a major concern.
Preparation
Water can be prepared by the ignition of any hydrocarbon or hydrogen. It can also be prepared by distillation of water from a lake or ocean, however none of the methods are economical due to the cheap price of water.
Projects
Water is a widely used solvent and is often the only solvent used in beginner inorganic chemistry, or it's more common term of "wet chemistry".
- Dissolving alkali metals in water
- Making hydroxides from metal oxides
- Hydrated crystals
- Ice crystals
- Cooling baths
- Oxoacids
- Generating hydrogen or oxygen via electrolysis
- Solvent extraction/washing
Handling
Safety
Ingestion of large amounts (really, really large amounts) of pure water can upset the osmotic balance is the body. The human body is composed mainly of water, though small amounts of any liquid, including water, can be fatal when inhaled, through a process commonly known as drowning.
It is recommended that a specific supply of distilled water is purchased.
Storage
Distilled water should be stored in closed bottles, away from heat or light sources to limit its evaporation, as well as to reduce its contamination with dust or other contaminants (otherwise you won't be needing pure water).
Disposal
Down the drain the water goes. Or in the garden. Just be sure it's clean water.
