A proposed laboratory scale cylindrical polymerization reactor to make high density polyethylene (HDPE) needs to be designed and constructed. The maximum design temperature and pressure of the reactor are 200 oC and 25 MPa, respectively. The reactor is used 4 times per day and must be designed for a minimum lifetime of 20 years. The inside diameter and wall thickness of the reactor are 300 mm and 10 mm, respectively. To meet safety regulations, a safety valve will be installed if the pressure exceeds 22 MPa, which will cause a maximum

law of conservation of matter

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).