Scientists use the periodic table to quickly refer to information about an element, like atomic mass and chemical symbol. The periodic table’s arrangement also allows scientists to discern trends in ...

Atomic number 6, atomic weight 12.01115. Manganese (Mn): Manganese is a brittle, metallic element that exists in the ore of pyrolusite. When making steel, it reacts with sulfur and helps to ...

was less than the atomic mass (average mass of the atom). For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass ...

The numbers of subatomic particles in an atom can be calculated from its atomic number and mass number. The periodic table - AQA Mendeleev made an early periodic table. In the modern periodic ...

Aluminum is a metal in group IIIA of the periodic table with atomic number 13, an atomic weight of 26.982, and a density of 2.70. It has a melting temperature of 660 C. The electronic configuration of ...