Se selenium
- 2. Selenium
Symbol- Se
Atomic number- 34
Atomic mass- 78.96
Melting point- 430°F
Boiling point- 1265°F
Number of protons/electrons- 34
Number of neutrons- 45
Classification- non-metal
Crystal structure- hexagonal
Density- 4.79 g/cm3
Color- gray, red, black
Natural state of matter- solid