Chemistry: Acids, Bases(Alkaline) and Salts

Chemistry: Acids, Bases and Salts

 

Acids:

• An acid is a chemical substance that has a sour taste.
• Many food items such as lemons, curd, vinegar and orange taste sour because of the presence of acid in them.
• Acidic Substances are the substances that contain acid in them.
• Natural Acids are the acids that occur in nature, for example, acids found in fruits are natural acids.

 

Bases:

• A base is a chemical substance that has a bitter taste and a soapy texture.
• Bases are found in different substances such as bleach, ammonia, washing powder and soap.
• Bases are also called Alkaline.

 

Neutral substances:

Neutral Substance is any substance which is neither acidic nor basic in nature.

 

Indicators

• We cannot taste every object and find its nature. Therefore, we use indicators.
• An indicator is a substance that can determine if another substance is acidic or basic in nature.
• The indicators indicate the presence of an acid or base in a substance by changing their colour.
• For Example, Turmeric, China rose petals and Litmus are some natural indicators.

Natural indicators: the indicators that occur in nature.

 

Litmus

• Litmus is a natural indicator which is obtained from Lichens.
• Litmus is available in a solution form and paper strips (red litmus and blue litmus paper).

 

Acid Rain

• When the rainwater has increased amounts of acids in it, it is called Acid Rain.
• The acid rain is formed because of the presence of air pollutants such as Nitrogen dioxide, Carbon dioxide and Sulphur dioxide in the air.
• These pollutants mix with the rainwater and form acids such as Nitric acid, Sulphuric acid and Carbonic acid respectively.
• The acid rain in severely affect the vegetation, animal life and even buildings of the region where it falls