If you're a student hoping to conquer chemistry—or just like chemistry as a hobby—web site Ptable gives you a browser based periodic table that lets you view element information, properties, orbitals, ...

THE periodic system of the elements, arrived at originally from the collation of facts of a chemical nature, has since been most strikingly reflected by most of the physical properties of the elements ...

Potassium is an alkali metal in group IA of the periodic table with atomic number 19, an atomic weight of 39.102, and a density of 0.86 Mg/m 3. Its melting point is 63.7 C, and it boils at 760 C. The ...

Calcium is a metal in group IIA of the periodic table with atomic number 20, an atomic weight of 40.08, and a density of 1.55 Mg/m 3. Its melting point is 838 C, and it boils at 1440 C. The electronic ...