GEOL 1100 Chapter Notes - Chapter 3: Muscovite, Conchoidal Fracture, Pyroxene
Document Summary
Ionic bond:atoms gain or lose outermost (valence)electrons to form ions. ionic compounds consist of an orderly arrangement of oppositely charged ions: covalent bond: valence electrons are shared by atoms. Both ionic and covalent bonds typically occur in the same compound: metallic bond:valence electrons are free to migrate among atoms. Weaker and less common than other bonds: isotopes and radioactive decay, mass number = sum of neutrons + protons in an atom. Isotope = atom that exhibits variation in its mass number (same element, but different masses, number of neutrons: unstable isotopes emit particles and energy in a process known as radioactive decay. Structure of minerals: minerals consist of an orderly array of atoms chemically bonded to form a particular crystalline structure. The internal atomic arrangement in ionic compounds is determined by ionic size: silicates: crustal minerals with oxygen and silicon as building blocks. Silicates classified as low or heavy based on ratio of silicon to oxygen.