beryllium atomic number
Beryllium: Symbol: Be: Atomic Number: 4: Atomic Mass: 9.012 atomic mass units: Number of Protons: 4: Number of Neutrons: 5: Number of Electrons: 4: Melting Point: 278.0Â° C: Boiling Point: 2970.0Â° C Density: 1.8477 grams per cubic centimeter: Normal Phase: Solid: Family: Alkaline Earth Metals: Period: 2: Cost: $530 per 100 grams