In chemistry, an alkali is an aqueous (from water) solution with a pH value of more than seven. The word 'Alkali' comes from the Arabic 'qali' meaning 'from the ashes' since ashes mixed with water used as cleaning products (such as soaps) are made of alkali materials.
An alkali is where a base is dissolved in water. Often it is the salt of an Alkali metal. An alkali is the opposite to an acid and can be neutralised (brought down to pH 7) by adding acid. It feels soapy. It is corrosive (it can burn your skin away).
The higher the number is over 7 on the pH scale the stronger the alkali is.
Highly soluble (can be dissolved) in water.
Have a bitter taste, turns red litmus paper blue, can conduct electricity due to the presence of mobile ions and is blue or purple on universal indicator

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