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Arrhenius’ Definition of Acids and Bases

Here, you will come across the Arrhenius theory of acid and base, the difference between acid and base accordingly, Arrhenius acid and Arrhenius base, and its limitations.

In 1884, a Swedish scientist named Svante Arrhenius worked on the theory of ionisation and, on that basis, tried to explain the characteristics of acids and bases. In the theory proposed by Svante, he explained how acid would react when mixed with water and how a base would react when kept along with water. As a result, it was seen that when we mix water and acid together, the acid will liberate H+ Ions into the solution, proving that acids have hydrogen content. On the other hand, if we mix water and a base, then the base present in the solution will liberate OH- Ions dissociated with water.

When an electrolyte is dissolved in water, it is separated into electrically positive and negative charged ions as cations and anions, respectively, considered ionisation. Arrhenius laboured to supply the distinction between acid and base based on the equal concept.  

Difference Between Acids And Bases

                                                                            ACIDS                                                  BASES

ACIDS   

BASES

Sour in taste

Bitter in taste

Not soapy to touch 

Soapy to touch

The blue litmus is turned red in the presence of acid

The red litmus turns blue in the presence of the base

Hydrogen ions are given out in an aqueous solution

Hydroxyl ions are given out in an aqueous solution 

Act as electron pair acceptor

Act as electron-pair donor

pH value is less than 7

pH value is more than 7

Electrophilic 

Nucleophilic 

Arrhenius Acids

According to Arrhenius, acid is any species that will extend the interest of hydrogen ions in an aqueous solution, or so he thought! When we make an aqueous solution of hydrochloric acid for all intents and purposes, the solution dissociates into hydrogen and chlorine ions as the products of the respective reaction, which is pretty significant. Since these consequences bring an increase in the formation of hydrogen ions in solution, hydrochloric acid, specifically, is an Arrhenius acid in a refined way. 

In practice, when the reaction takes place on a laboratory basis, the positively charged protons normally react with the surrounding water molecules to form hydronium ions, contrary to popular belief, or so they mainly thought. And this is the actual happening at the time of reaction, but the scientists take the hydronium ions equivalent to hydrogen ions. Thus the result, which is most common among everyone, is obtained. This response can be demonstrated through a very common example will that will show how the above information can be proven correct and in reality, be written as follows:

H+ (aq) + H2O (l) → H3O+ (aq)

As an instant result, the formation of hydronium ions is seen when acid dissociates with water. This is mostly used as scientists take into account that hydrogen ions and hydronium ions are on a similar basis while talking about a chemical reaction.

Arrhenius Bases

An Arrhenius base is a species that dissociates with water to give out hydroxyl ions. It increases the concentration of the hydroxyl ion in the aqueous solution.

Arrhenius base example: An example of it is the highly soluble sodium hydroxide. Sodium hydroxide dissociates in water as follows:

NaOH (aq) → Na+ (aq) + OH(aq)

Arrhenius Acid + Arrhenius Base

When an acid and a base endure a chemical response and form a bond with each other during the process, the reaction is known to be a neutralisation reaction. The products eventually bought as a result are water and salt. 

When in the course of the dissociation of acid into water produces hydrogen ions and on the other hand the dissociation of the base into water produces hydroxide ions, this offers us the primary expertise about how the water and salt are created for the duration of the response of both acid and base. 

The hydrogen ion produced from the acid aspect and the hydroxide ion produced from the base side mix together, and as a result, we attain water. The left out species of acid and base join hands to shape the salt. 

Suppose, for example; we combine an aqueous solution of hydrofluoric acid and lithium hydroxide, then the following reaction will take place:

HF (aq) ⇄ H+ (aq) + F(aq)

And as a result, the products formed will undergo the ascending reaction in order to form water and salt as the final product.

LiOH (aq) → Li+ (aq) + OH (aq)

Limitation Of Arrhenius Theory Of Acids And Bases :-

This theory is only applicable to acids and bases in the aqueous solution.

H+ (aq) + OH (aq) →H2O (l)

Conclusion

A scientist named Svante Arrhenius gave the popular ” Arrhenius theory of acids and bases”, their respective characteristics in the presence of aqueous solution and how ionisation theory is related to it, for which he received a Nobel Prize as well. But the theory was limited to the aqueous solution and could not satisfy the characteristics of the non-aqueous solution, which is the limitation of Arrhenius theory of acid and base.

 
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How would you define the Arrhenius theory of acids and bases with respect to ionisation theory?

Ans : In the theory proposed by Svante, he explained how acid would react when mixed with water and...Read full

What is Arrhenius acid? And what lazy belief is taken into account regarding product formation?

Ans : According to Arrhenius, acid is any species that will extend the interest of hydrogen ions in...Read full

What are the limitations of Arrhenius theory of acids and bases?

Ans : This theory is only applicable to acids and bases in the aqueous solution. When the reaction ...Read full

Explain Arrhenius Bases.

Ans : An Arrhenius base is a species that dissociates with water to give out hydroxyl ions. It incr...Read full