Chemistry
Basis of Periodic Table
What is the basis of the periodic table? The periodic table also makes known fascinating patterns and exceptions. For example, noble gases on the far right have all their “energy levels” occupied, making them exceptionally stable and inactive. Groups like halogens are electron-attracted, always looking for other atoms to fill their empty “orbitals.” The fundamental … Read more
Laboratory Principles: Dress, Safety Glass, Mask and Hand Gloves
Laboratory is a very important place, where research is carried out for human welfare. Chemical laboratory is unique place to know and develop something new. Different types of chemicals are generally used in the laboratory. Among these, some are volatile, hazardous and very harmful to human health. The consequences could be severe if someone does … Read more
NEUTRON: Discover
In 1932, J. Chadwick discovered another subatomic particle which had no charge and a mass nearly equal to that of a proton. It was eventually named as neutron. Neutrons are present in the nucleus of all atoms, except hydrogen. In general, a neutron is represented as ‘n’. The mass of an atom is therefore given by the sum of the masses … Read more
How are Electrons Distributed in Different Orbits (Shells)?
The distribution of electrons into different orbits of an atom was suggested by Bohr and Bury. The following rules are followed for writing the number of electrons in different energy levels or shells: (i) The maximum number of electrons present in a shell is given by the formula 2n2, where ‘n’ is the orbit number … Read more
ATOMIC NUMBER
We know that protons are present in the nucleus of an atom. It is the number of protons of an atom, which determines its atomic number. It is denoted by ‘Z’. All atoms of an element have the same atomic number, Z. In fact, elements are defined by the number of protons they possess. For … Read more
What is covalent bond?
The bond formed by sharing of electrons to obtain stable electron configuration at the outermost energy level is called covalent bond.
What is molecular formula?
A molecular formula is a chemical formula which consists of the chemical symbols for the constituent elements followed by numeric subscripts describing the number of atoms of each element present in the molecule.