Author: Rimsha Nazir
INTRODUCTION
Have you ever wondered what makes lemons taste sour and soaps slippery? From the sourness of citrus fruits to the effectiveness of soaps, acids and bases play a significant role in our daily lives. Acids and Bases are the fundamental chemicals that are present everywhere, from the food we eat to the soaps and alkalies we use in our daily lives.
In this blog, we will dive into the comprehensive understanding of acids and bases by exploring the different concepts of acids and bases, their properties, and importance in our daily lives.
Whether you’re a student learning about acids and bases for the first time or someone looking for a refresher, this post will break down everything you need to know, from definitions and properties to real-world applications.
ACIDS
- The word “Acid” is derived from the Latin word “Acidus” which means “Sour”.
- Acid is a Chemical substance that gives off protons (H+) ions in water and has a sour taste.
- For example, Hydrochloric acid, Sulphuric acid, Carbonic acid, etc.
BASES
- Bases are also known as “Alkalies”.
- Base is the chemical substance that gives off hydroxide ions and has a bitter taste.
- For example, Sodium hydroxide, Potassium hydroxide, Ammonium hydroxide, etc.
PROPERTIES OF ACIDS AND BASES
| Name of Properties | Acids | Bases |
| Taste | Sour | Bitter |
| pH-Value | Less than 7 | More than 7 |
| Effect on Litmus Paper | Turns blue litmus paper red | Turns red litmus paper blue |
| Electrical Conductivity | Can conduct electricity from their solutions | Can conduct electricity due to the presence of free Hydroxide ions |
| Corrosiveness | Corrosive in concentrated forms | Non-corrosive except concentrated forms of NaOH and KOH |
| Reaction with Metals | React explosively with metals | Not react with metals |
| Slipperiness | Non slippery | Slippery |
THEORIES OF ACIDS AND BASES
There are different theories or concepts related to Acids and Bases. These are the following:
1. ARRHENIUS THEORY OF ACIDS AND BASES
According to Arrhenius theory,
- Acid is a specie which yields hydrogen ions upon dissociation in aqueous solution. While
- Base is a specie which yields hydroxide ions upon dissociation in aqueous solution.
2. BRONSTED-LOWERY THEORY OF ACIDS AND BASES
According to this theory,
- Acid is a specie that have the ability to lose one or more protons and form a conjugate base.
- Base is a specie that have the ability to gain one or more protons and form a conjugate acid.
3. LEWIS THEORY OF ACIDS AND BASES
According to this theory,
- Acid is a specie that is an electron pair acceptor, e.g., BF3 accepts an electron pair.
- Base is a specie that is an electron pair donor; e.g., NH3 donates an electron pair
4. LUX-FLOOD CONCEPT OF ACIDS AND BASES
According to this concept,
- Acid is a specie which is an oxide ion acceptor, e.g., SiO2, CO2, P2O5, etc.
- Base is a specie which is an oxide ion donor, e.g. CaO, MgO, etc.
5. USANOVICH CONCEPT OF ACIDS AND BASES
According to this concept,
- Acid is a specie that reacts with base, gives up cations, or accepts anions or electrons.
- Base is a specie that reacts with an acid, gives up anions or electrons, or combines with cations.
pH SCALE-MEASUREMENT OF ACIDITY AND BASICITY
The acidity of an acid and basicity of a base are measured by a handy tool (pH scale), which tells how acidic or basic a solution is. It has a range from 0 to 14. The pH scale is the measure of hydrogen ion concentration.
pH = -log of [hydrogen ions]
- If the pH value < 7, then the solution is acidic (lower pH = strong acid)
- If the pH value = 7, then the solution is neutral. e.g., water.
- If the pH value > 7, then the solution is basic (higher pH = Strong base)
STRONG ACIDS VS WEAK ACIDS
- Strong acids are those which completely dissociate in water to yield a large amount of hydrogen ions. e.g., HCl, HNO3, H2SO4, etc.
- Weak acids are those that are not completely ionizable in water and yield a small amount of hydrogen ions. e.g., Citric acid, acetic acid, etc.
STRONG BASES VS WEAK BASES
- Strong bases are those that completely dissociate in water to yield a large amount of hydroxide ions. e.g., NaOH, KOH, Ca (OH)2 etc.
- Weak bases are those which are not completely ionizable in water to yield a large amount of hydroxide ions. e.g. NH4OH, Al (OH)3 etc.
MEASUREMENT OF THE pH OF A SOLUTION
The pH of the solution is measured by
- Universal indicator
- The pH meter
- The pH papers
- The pH indicators
NEUTRALIZATION REACTION
When an acid reacts with a base, then a salt (a neutral compound) is formed along with the formation of the water molecule; this reaction is called a neutralization reaction.
APPLICATIONS OF ACIDS AND BASES
Acids and bases are widely used chemicals in our daily lives. Some applications of acids and bases are the following:
Biological Applications
Acids and bases are widely used in biological processes such as digestion, metabolism, etc.
Industrial Applications
Acids and bases are used for various industrial processes, such as for the production of fertilizers, dyes, and pharmaceuticals.
Environmental Applications
Acids and bases are widely used to treat wastewater, remove pollutants, etc.
Applications in Food Industry
Acids and bases are widely used in the food industry for flavoring, as a preservative to enhance the flavor.
CONCLUSION
One of the major chemistries and their roles in daily life is, of course, in influencing taste in foods and industrial processes. A variety of theories in science have attempted to explain the properties of acids and bases. The pH scale classifies substances as acidic or basic, providing vital information for their application in medicine, foods, agriculture, and environmental management. Knowing how acids and bases operate will enable one to safely and effectively use them in everyday situations.
Read More: Sulfonamide Drugs: A Comprehensive Guide To Their Uses And Mechanism
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