Everything we see around us, air, water, food, even our own bodies is made up of tiny particles. These particles are called atoms and molecules. If you’re a student preparing for exams like NEET, JEE, understanding the difference between an atom and a molecule is one of the most important basics in chemistry. It’s a topic that often seems simple but forms the foundation for many other concepts. In simple terms, an atom is the smallest unit of matter that cannot be broken down further in a chemical reaction. When two or more atoms join together, they form a molecule. For example, oxygen gas we breathe is made up of oxygen molecules (O2), and each of those molecules is made up of two oxygen atoms. In this article, we’ll break down the definitions, differences, and examples of atoms and molecules to help you understand them clearly and remember them easily for your exams.

What is an Atom?

The smallest part of an element that cannot be ruptured chemically is called an atom. The atom is further composed of two sections; the outer part contains electrons in revolving condition around the inner part, called the nucleus, composed of protons and neutrons. Protons resemble hydrogen ions, and each proton carries a positive charge. Neutron has a mass but does not show a charge. 

The electrons are negatively charged, and their numbers are decided by the number of protons in the nucleus, as the charge balance is necessary to maintain the neutral entity of any element. 

There are a lot of controversies around electrons regarding their nature. A few scientists support its particle nature, and some treat it like a charged wave. In modern research, electrons have been accepted as possessing dual character; particle and wave natures are observed in electrons.

• An atom is a small part of an element that contains each and every property of an element. 
• It is neutral in nature. 
• It has mass, volume and density. 
• Stability of an atom depending on the proton neutron ratio.
• Unstable nuclei always remit energy as ray to achieve a more stable atomic nucleus. 

What is Molecule?

A molecule is formed when two or more atoms join together. These atoms can be of the same element or different elements. Molecules are the next step after atoms; they make up everything around us, from the air we breathe to the food we eat. Atoms don’t always like to stay alone. They often combine with atoms to become more stable. This combination happens through something called a chemical bond. When atoms bond, they form a molecule, For example, a water molecule (H2O) is made when two hydrogen atoms join with one oxygen atom. In the same way, an oxygen molecule (O2) is made up of two oxygen atoms, and carbon dioxide (CO2) is one carbon atom and two oxygen atoms. Molecules can be simple, like O2 (oxygen), or more complex, like glucose (C6H12O6). But no matter how big or small, every molecule starts with atoms coming together. 

Characteristics of Molecule

These are the different characteristics of molecules:

• Molecules that occur in different forms in nature are solid, liquid and gases.
• Molecules can have either high solubility or either it can have low solubility.
• They are poor conductors of electricity as they do not conduct electricity.
• In comparison to ionic compounds, molecules have lower melting points or higher boiling points.
• In molecules, many solids join together to form a diamond-like network crystal.

Difference Between Atom and Molecule

These are the differences between atoms and molecule

Common Examples in Daily Life

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