Element vs Molecule
Atoms are the tiny units which collect up to form all the existing chemical substances. Atoms can join with other atoms in various ways, thus form thousands of molecules and other compounds. According to their electron donating or withdrawing abilities, they can form covalent bonds or ionic bonds. Sometimes there are very weak attractions between atoms. A chemistry student should have an idea about the two basic concepts, “element” and “molecule” and how to differentiate between two.
We are familiar with the word “element,” because we learn about them in the periodic table. There are about 118 elements given in the periodic table according to their atomic number. An element is a chemical substance which consists of only a single type of atoms, hence they are pure. For example, the smallest element is the hydrogen, and silver, gold, platinum are some of the commonly known precious elements. Each element has an atomic mass, atomic number, symbol, electronic configuration, etc. Although most of the elements are naturally occurring, there are some of the synthetic elements like Californium, Americium, Einsteinium, and Mendelevium. All the elements can be broadly categorized into three categories as metal, metalloids and non metals. Further, they are categorized into groups and periods based on more specific characteristics. Elements in the same group or periods share certain common characteristics, and some properties may change sequentially when you go through a group or period. Elements can be subjected to chemical changes to form various compounds; however, elements cannot be further broken down by simple chemical methods. There are atoms of the same element with different number of neutrons; these are known as isotopes of an element.
Molecules are made up by chemically bonding two or more atoms of the same element (e.g.: O2, N2) or different elements (H2O, NH3). Molecules don’t have a charge, and the atoms are bonded by the covalent bonds. Molecules can be very large (hemoglobin) or very small (H2), depending on the number of atoms that are connected. The type and number of atoms in a molecule are shown by the molecular formula. The simplest integer ratio of atoms present in a molecule is given by the empirical formula. For example, C6H12O6 is the molecular formula of glucose, and CH2O is the empirical formula. Molecular mass is the mass calculated considering the total number of atoms given in the molecular formula. Each molecule has its own geometry. The atoms in a molecule are arranged in the most stable manner with specific bond angle and bond lengths to minimize the repulsions and straining forces.
What is the difference between Element and Molecule?
- Elements are pure substances, which consist of only a single type of atom.
- Molecules may contain two or more atoms of the same element or different elements.
- The properties of an element often change completely when they are part of a molecule.
- There are strong covalent bonds between atoms of the molecule, but in elements, there can be metal bonds or weak, non-covalent forces.