Everything in this world that occupies space is defined as the matter. The matter can be further split into two main categories, pure substance or mixture. Either the mixture or the pure substance, all the matter is made up of the atom, which is the smallest particle of the chemical element. People often found it difficult to differentiate between the terms like atom and molecule as they are closely related. As mentioned above, the atom is the smallest unit of a chemical element; it should be noted here that, two or more atoms combine to form the molecule. When identical atoms get amassed, it is known as the molecule of an element, and when atoms of two different elements get combined, they are known as the molecule of the compound.
What is Atom?
Atom is the smallest part of the chemical element that can exist in the Free State and also possess the chemical properties of its element. The atom is like the cell, which is the smallest structural and functional unit of the living. In other words, we can say that all the objects around us i.e. table, chair, sofa are made up of atoms. The physical and chemical properties of the certain element are the same in the atom of that matter. Atom is a kind of unit of the matter as everything that occupies space and has mass is known as matter, and at the same time, the atom is the smallest unit that can exist in the Free State. The atoms are less stable units as compared to the molecule, and to attain stability, they are highly reactive and form an immediate bond. Atoms may or may not exist in the free state, but the molecules always exist in the free state. The atoms comprise of the subatomic particles like nucleus, neutrons, protons, and electrons, although atom doesn’t get divided into its sub-atomic particles. The nucleus is the center most of the atom, around which proton and electron revolve. It should be kept noted that; the proton carries the positive charge, whereas the electron carries the negative charge.
What is Molecule?
Two or more than two atoms combine to form the molecule, which exists in the free state. The molecules can further get split into the atoms it is comprised of. Molecules are more stable than the atoms so they are less reactive and don’t take part in the chemical reaction. The chemical bond is formed in between the atoms, to form the molecule. Specifically, it is the covalent bond that is formed between the atoms to form the molecules. Or in other words, we can say that the exchange of electrons between the atoms takes place to form the molecule. When identical atoms get amassed, it is known as the molecule of an element, and when atoms of two different elements get combined, they are known as the molecule of the compound. The combination of atoms in fixed proportion is the complimentary task to make up the molecule. For instance, as we know that H2O is the formula of one molecule of water. Two atoms of Hydrogen and one atom of Oxygen get combined in the fixed proportion to form one molecule of water. But if the proportion of any of the element changes, the water molecule won’t be formed.
Atom vs. Molecule
- Atom is the smallest unit of the chemical element, whereas two or more atoms combine to make up the molecule.
- Atom may or may not exist in the free state while molecule always exists in the free state.
- The atom is reactive as it is less stable as compared to the molecule. Contrary to this, the molecule is less reactive and more stable.
- The atom comprises of the subatomic particles like neutron, electron, and proton. Conversely, the molecule comprises of two or more atoms.
- The atom can’t be further divided, whereas the molecule can be further divided into atoms.