The periodic table of elements, devised by Russian chemist Dmitri Mendeleev, is a two-dimensional array of the chemical elements, ordered by atomic number and arranged 18 across by orbitals.

Four new elements are about to be added to the periodic table: nihonium (Nh, element 113), moscovium (Mc, element 115), tennessine (Ts, element 117), and oganesson (Og, element 118). When you say ...

Periodic Puzzler Help This puzzle shows many of the elements used to make transistors. The finished puzzle is a section of the periodic table, so the numbers on each tile are their atomic numbers ...

On rationalising the periodic table, the NCERT said that discussion about basic concepts such as elements, symbols, and formation of compounds, atoms and molecules had been dealt with in Class 9.