As per basic knowledge, we know that chemistry is the subject that deals with various substances, atoms, molecules and compounds. The first thing that enters our minds on hearing the subject chemistry is acids. We know that the subject chemistry also comprises of various chemical reactions, chemical compounds, which are either acids or bases or salts. These are the substances that we come across in our day to day life activities. This article showcases a few basics and an introduction to acids and bases.
What are acids and bases?
In general, we can say that an acid is any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance. A base is a molecule or ion able to accept a hydrogen ion from an acid. Few other theories have been discovered which describes acids and bases as per those theories. Acids are chemical substances that are distinguished by a sour taste in an aqueous medium. On the other hand, bases are chemical substances that are characterised by a bitter taste and are slippery to the touch.
pH value for acids and bases
pH can be described as an abbreviation of the power of hydrogen-or, more fully, the concentration of hydrogen ions in a liquid. The pH of a solution ranges from 0 to 14.
Solutions having a value of pH ranging 0 to 7 on the pH scale are called acidic, and the value of pH ranging 7 to 14 on the pH scale are called basic solutions. Solutions having the value of pH equal to 7 on the pH scale are called neutral solutions.
Strong and weak acids or bases
There are two classes of acids they are strong and weak acids. The dissociation constant helps in determining the strength of an acid. The dissociation constant is denoted by Ka and is the major factor responsible for knowing which acid is strong and which one is weak.
- A strong acid is an acid that is completely dissociated in an aqueous solution. It is a chemical substance with a high capacity to lose a proton, H+. In water, a strong acid loses one proton, which is captured by water to form the hydronium ion.
- A weak acid is an acid that is partially dissociated into its ions in an aqueous solution or water. In contrast, a strong acid fully dissociates into its ions in water.
- A strong base is a compound that has the ability to remove a proton from a very weak acid. Or they completely dissociate into their ions when in water.
- Weak bases possess incomplete dissociation when in water. The aqueous solution comprises both the weak base as well as its conjugate acid.
Properties of Acids and Bases
Acids have some special properties. Few properties of acid are listed below:
- Acids are corrosive in nature.
- The taste of acid is sour
- Acids are good conductors of electricity.
- Acids reacting with metals produce hydrogen gas.
- Acids are soluble in the universal solvent that is water.
- Acids turn blue litmus paper into a red colour.
Acids react differently with all substances depending upon their characteristics. The acidity of a particular molecule is described by the pka value of the substance. Metals, non-metals and halogens all have a wide range of reactions with acids.
Bases have some special properties. Few properties of bases are listed below:
- The taste of the base is bitter.
- Bases are bad conductors of electricity.
- Bases release a hydroxide ion in a water solution.
- Bases turn red litmus to blue.
Applications
Acid and bases are used widely in day to day life activities. A few of the applications are listed below:
- Citrus fruits such as oranges and lemon contain citric acid.
- The soap contains wide molecules of salts and bases.
- Acids are also used as preservatives in storing food and pickles, such as sodium benzoate or vinegar.
- Bases are used in cleansing agents such as soaps and detergents.
Acids and bases have a wide range of applications in pharmaceutical companies, factories to produce cosmetics, goods, food preservatives, and also in the packaging industry. Each and every consumable product contain a small amount of edible acid and bases.