What are Acids?
The acid in the Latin language means sour. Acids are substances that contain hydrogen and produce hydrogen ions in aqueous solutions. Acids are commonly found in citrus fruits like lemon, tamarind, etc. Citric acid is found in lemon and tartaric acid is found in tamarind. Some of the main acids are hydrochloric acid, sulfuric acid, nitric acid, oxalic acid, acetic acid, formic acid, etc.
We can see many examples of acid in our normal life like the sour taste of all citrus fruits and foods is due to acids like citric acid found in lemon, orange, etc.; acetic acid is found in vinegar, Malic acid is found in apple, tannic acid is found in tea, phosphoric acid is found in carbonated soda, besides hydrochloric acid is used in our body to digest food.
Examples of Acid
Apart from foods, there are many such acids which are used by us domestically or industrially such as sulfuric acid, nitric acid, hydrochloric acid, hydroiodic acid, hydrobromic acid, chloric acid, aqua regia etc.
Interesting Facts about Acids
Acids are sour.
Good and strong acids are good conductors of electricity.
Hydrogen is present in all types of acids.
Acids turn blue litmus red.
The pH level of acids is between 0 and 6.
Acids produce hydrogen gas when reacted with active metals.
Acid carbon dye on reaction with carbonate oxides generate gas. Most acids are corrosive, meaning they are metals. But have the ability to rust or melt them.
Acids react with bases to form salts and water, in this reaction the acid destroys all the chemical properties of the base and also loses its acidity.
An interesting fact about amino acids is that they can also be used by the body as a source of energy.
Litmus Paper and pH scale as an Indicator
Fun Facts about Alkalis
Interesting Facts about Bases (Alkalis)
Alkali is those compounds of metals or radicals that behave like metals, which react with acids to form salts and water.
Alkali is pungent or bitter.
Alkali feels as smooth as soap to the touch.
A strong base is a good conductor of electricity.
The base turns red, litmus blue, and methyl orange in yellow.
Alkali can dissolve oil and sulphur.
Bases turn phenolphthalein pink.
Bases usually precipitate metal hydroxides when added to a salt solution.
Solved Questions
1. How does the colour of litmus change in acidic and alkaline mediums?
Ans: The colour of litmus is red in an acidic medium and blue in an alkaline medium.
2. Write one difference between acid and base.
Ans: Difference between an acid and a base:
Acid - An acid is a substance whose aqueous solution tastes sour.
Base - A base is a substance whose aqueous solution tastes bitter.
Learning By Doing
Write True or False.
Acids are sour.
Good and strong acids are bad conductors of electricity.
Acids turn blue litmus green.
The pH level of acids is between 0 and 6.
Hydrogen is present in all types of acids.
Summary
Acids are substances that contain hydrogen and produce hydrogen ions in aqueous solutions. Acids are commonly found in citrus fruits like lemon, tamarind, etc. Acids are sour. Good and strong acids are good conductors of electricity. Hydrogen is present in all types of acids. Acids turn blue litmus red. Acids react with bases to form salts and water.
FAQs on Facts About Acids
1. Write two uses of Acids.
The uses of acids are as follows:
Sulfuric acid is used in the refining of petroleum to make explosives and as a liquid in lead accumulator batteries.
Formic acid is used in fruit preservation and as a bactericide. Formic acid is a toxic substance in animals like ants, scorpions, bees etc.
2. Write two nutrition facts about amino acids.
The two nutrition facts about Amino Acids are listed below:
The body uses amino acids to make proteins, to help the body break down food, grow, repair body tissues, as well as help the body with many other functions.
Amino acids can also be used by the body as a source of energy.
3. Which synthetic indicators are used to test acids and bases?
Methyl orange and phenolphthalein are used to test acids and bases.
