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Acids, Bases and Salts

If we have studied chemistry well in the middle classes of the school. Then it is very easy to say that we will have a lot of ideas about the concept of acids, bases and salts.

The concept of acids, bases and salts is one of the most important concepts of chemistry and if we are able to master them early, then it is sufficient to say that we will have a command of physical chemistry. Physical chemistry is that section of chemistry that includes all types of numerical parts and problems that we have to deal with. Now, let us understand the concept of acids, bases and salts in depth. 

Acids 

Now if we want to discuss the concept of acids in detail we can start by saying that acids are that type of molecules that are always capable of donating a proton. In the junior classes we have also learnt about the fact that if on checking we come to know that a substance has a pH of less than seven on the scale then we can say that the substance is an acid. The acids generally turn the litmus red in colour. 

Some of the very common examples of acid are sulphuric acid and nitric acid. These acids are two of the three most strong acids that we know till date. Now many scientists have had their say in this concept already and those scientists formed what are now called the Lewis Acids and the Bronsted Lowry Acids. These types of acids are the ones that have been newly formed and they both involve the hydronium ions in it. One more type of acid that exists is called the Arrhenius Acid. 

Aqueous Solutions 

One of the most common but important reactions in this concept is that if we add the hydroxide ion to the hydronium ion then we end up getting two water molecules and the interesting fact is that we get both those molecules in the liquid form itself. One of the most interesting facts about acids is that if there is a molecule of acid and we dissolve it, we end up getting the base and the acid of that molecule separated. 

The acid molecule that is separated is called the Conjugate Base and the base molecule that is separated is called the Conjugate Acid. The reaction that we have talked about in the above paragraphs is one of the most important reactions and is named Protolysis. In this process the main equation requires the division of the acid and the base which are formed separately and are in turn divided by the whole product in it. 

Different types of acids 

The two major types of acids are monoprotic acids and polyprotic acids. Monoprotic acids are the acids that have the capability to donate only a single proton. The interesting fact about monoprotic acids is that the one proton that is counted is done per a single molecule itself. Some of the examples of the monoprotic acids are nitric acid and hydrochloric acid, if we consider the strong acids, and carboxylic acid and the benzoic acid, if we consider the weak acids.

The next type of acid is the polyprotic acid. Polyprotic acids are the acids that are capable of producing more than one proton per molecule. There are different names for the acids that give out two or three protons per molecule and they are called the Dipolar and Tripolar acids. The acids which have large formulas are also categorised under these types of acids themselves. Those acids are generally the protein and the nucleic acids. 

Bases 

A base is that substance in chemistry that has the ability to give a proton to any substance in most cases an acid that is in need of it. As we discussed in the above paragraphs, usually the acids give a red colour when tested on the pH scale and they have a pH below seven. Now bases are the substances that have a pH higher than seven and give the colour blue whenever tested on litmus paper. 

Now apart from the acids and the bases there are substances also that are called the neutral substances as they have the pH of exactly seven and they give out the green colour. The most commonly known neutral substances are blood and water. Some of the examples of bases are the hydroxides and the hydroxide ions. 

Reactions of the bases

Bases when reacted with water generally produce water molecules and a conjugate base. In the above equation usually the water molecule that is produced as a result of the reaction and the conjugate proton that is produced fight for the extra proton that has been obtained. 

Salts 

Salts are one of those substances about which not much information has been gathered yet when we compare it to acids and bases. The salts can be of various types but the types that are known the most are the acidic salts and the basic salts. Acidic salts are the salts that produce acids when dissolved in water and the basic salts are the salts that produce bases when produced in water. 

There are essentially two types of salts if we are to categorise them strength wise and they are called the strong salts and the weak salts. Strong salts are the salts that produce strong acid upon electrolysis and the weak salts are the salts that produce weak acid upon electrolysis.

Conclusion

The concept of acids, bases and salts is one of the most important concepts in the field of physical chemistry. More the knowledge we have about these substances, the more we can enjoy chemistry.