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Electrical ConductivityPure water does not conduct electricity.
But then why are we often warned about the danger of electrocution when using
electrical appliances near water?
Electrical ConductivityIt’s because water itself does not conduct
electricity, instead it is substances dissolved in the water.
Some substances can allow an electric current to flow through a solution (when they are dissolved
in water or another solvent). These substances are called electrolytes.
One example of an electrolyte is table salt.
ElectrolytesWater in oceans, rivers and lakes contain electrolytes in
varying concentrations. This difference in concentration is among the characteristics that distinguish the fresh water
of rivers from the salt water of the sea. Many living organisms need the electrolytes in water to survive.
AcidsExamples of Acids are: fruit juice, soft
drinks, and the gastric juices secreted by the stomach. We can identify acids by
their sour taste.
BasesBases are found in many cleaning products and in some heart-burn medication. Blood and salt water are also slightly basic. Basic
solutions have a bitter taste.
SaltsThe best known salt is table salt. Most salts
are made up of a metal and one or more nonmetals.
PH LevelOne property that distinguishes acidic,basic
and neutral solutions is their pH. The pH sclaes ranges from 0 to 14.
If the pH is <7 (less than 7) the solution is acidic.If the pH = 7, the solution is neutral.
If the pH is > 7 (greater than 7) the solution is basic.