Atom and Molecule

Atoms and molecules form the basic unit of any substance. However, they both have many differences between them. We’ll see soon how. In Chemistry, the properties of matter are shown by atoms and molecules. A molecule can be called a combination of atoms or a set of atoms. Where an atom is the smallest unit of any substance. The word Atom is taken from the Greek word indivisible which means a particle that can not be further divided. However, its molecules can be divided. Let us learn more about the distinction between an atom and a molecule by various means.

Atoms and Molecules: Definition

Atoms: An atom is often referred to as the fundamental unit of any substance which further can not be divided into any more parts. An atom contains neutrons, protons and electrons. Where neutrons are neutrally charged, protons are positively charged and electrons are negatively charged. Though it contains some more parts inside it, those cannot be divided physically or chemically. The collection of protons and neutrons inside an atom is called the nucleus of an atom and is placed at the centre of it. And electrons rotate about atoms in various orbits. Even the mass of protons and neutrons is almost equal. Atoms are always present in a spherical shape.

Examples of atoms are Sulphur atom (S), Chlorine Atom (Cl), etc.

Molecules: When two or more atoms combine with any of the bonds, namely, a covalent bond or hydrogen bond or ionic bond or any other bond. They are referred to as molecules. So, a molecule is a set of two or more atoms. A molecule is also a very small particle in any substance, if we break something it will still show the characteristics of that material. Because molecules are substances or particles that depict the characteristics of any substance or material. The shape of a molecule can be different from each other. They may have either spherical shape, tetrahedral shape, etc. It is based on the number of bonds an atom has and the number of lone pairs of electrons it contains.

Examples of molecules are Hydrogen (H2), Sulphuric Acid (H2SO4), Hydrochloric Acid (HCl), etc.

Characteristics of Atoms and Molecules

Atoms

• An atom’s centre is always positively charged
• An atom contains protons with a positive charge, neutrons with no or neutral charge, and electrons with a negative charge
• The overall charge of an atom is zero and is neutral
• An Atom’s size is defined by the radius of its outer shell
• The number of neutrons and protons in an atom are equal
• An atom contains its atomic number which is the number of protons in that atom-containing positive charge
• They are naturally unstable and very reactive
• This condition applies to only non-noble elements

Molecule

• A molecule defines the characteristics of a material or a substance
• It may form crystal form by attaching to solid forms
• It can have its solubility level either high or low
• They determine their melting point depending on the number of bonds they have and their ionic compounds
• They are naturally stable particles  
• They do react easily

Conclusion

To sum up, an atom is the smallest unit of any substance or material, and a molecule consists of sets of atoms, either two or more two. Atoms are indeed the basic components of molecules, and they are smaller than a molecule. When you contrast the sizes of atoms and molecules, you’ll see that atoms seem smaller when compared to them. It is impossible to split an atom into any smaller part since atoms are the fundamental units of molecules. It is made up of electrons, protons and a nucleus. Molecules, on the other side, are readily subdivided into atoms that might be of the same or part of a group. Even atoms and molecules have different sizes and shapes.