CHEM 222 Lecture Notes - Time On Earth, Mare Imbrium, Radionuclide

• School: McGill University
• Department: Chemistry
• Course: CHEM 222
• Professor: Karine Auclair

Document Summary

Molecules stoichiometrically precise relative composition of elements (ie. water has 2 atoms of h for every atom of o) Minerals do not follow a precise stoichiometry. More like structures in which certain atoms can be easily secured. The minerals compose rocks in the earth"s crust are typically silicates, oxides, and sulfides with various metallic cations. Silicates and oxides form lithophiles ( like to be rock) Chalcophiles are metallic elements that combine easily with sulphur. Olivine = one of the most important minerals in the solar system (ranges between mg2sio4 and fe2sio4, allowing for any possible mixed composition of magnesium and iron. The physical properties of olivine change as the mg/fe ratio changes. Forsterite (mg-rich olivine) freezes at a much higher temperature than. Quartz (sio2) = a mineral which is a common constituent of rocks. In pure form it is a colourless crystal though it can take on colours.