GL101 Lecture Notes - Lecture 7: Mohs Scale Of Mineral Hardness, Valence Electron, Crystal Habit
Document Summary
Protons (positive charges) and neutrons (no electrical charges) Negatively charged particles that surround the nucleus. Atomic number number of protons in the atom. Atomic weight approximately the total number of protons and neutrons in the nucleus. Valence electrons outer-most electrons in the shell. Chemical bonds strong attractive forces, forms compounds. Covalent bonds bonds that share electrons. Ionic bonds one atom (mostly) gives up electron(s), another receives them. External expression of the orderly internal arrangement of atoms. Crystal growth is often interrupted because of competition for space and rapid heat loss. Appearance of a mineral in reflected light. Other terms, such as vitreous, silky, or earthy, are used to further describe non- metallic lustre. Colour can be obvious (yellow, pink, etc. Example: quartz clear, white, rose, smoky, purple, etc. Colour of a mineral in its powdered form, when rubbed on an unglazed porcelain tile (streak plate)
