For example, the atomic number of sodium is 11. Every sodium atom has 11 protons and 11 electrons. It has 11 positive charges and 11 negative charges. The mass number of an atom is its total ...

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 ...

For example, the mass number of argon atoms and calcium atoms can both be 40. The atomic number of a chlorine atom is 17 and its mass number is 35. Calculate the number of protons, neutrons and ...

The periodic table is a well-organized chart that contains all the known elements in the universe. These elements are ...

according to increasing atomic number. 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 ...