Water Testing

Alkalinity is the capacity of water to neutralize (buffer) an acid (The measure of how much acid can be added to a liquid without causing a significant change in pH). Water can consequently be relatively low in pH but still have a high alkalinity.

pH itself being a scale from acidic through to basic, alkaline can be used interchangeably with basic (unless you're in college, where the use of alkaline to describe a basic ph will ussually result in a dirty look from your lecturer), but it's a good idea to get into the habit of referring to high pH's as being basic, it saves a lot of confusion.
 
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