chem Essay Example For Students

chem Essay Problem: What substance is must suitable for growing crystals?Methods and Materials:In a jar add to very hot water whichever substance you are workingwith until saturation is reached, in this case Epsom salt, salt, sugar, andbaking soda. Pour the solution off into a clean jar, leaving behind anyundissolved substance. Suspend a thin thread into the center of the jar. Ifyou are using the jar lid, screw it on, this is to control the rate of evaporation. Let sit, then after 15 minutes, swish the jar a bit. Swish it again 15 minuteslater, then one final time an hour later. Set the jar where it wont be disturbed. Depending on the substance used, the crystals should begin to grow in anhour or so, and continue to grow for from a day to several days. -Salt Epsom-Salt-Sugar-Water-Containers-String-Pieces of metal-Bicarbonate of soda (baking soda)Research:A crystal is defined as a solid body bounded by natural plane faces thatare the external expression of a regular internal arrangement of constituentatoms, molecules, or ions. The particles in a crystal occupy positions withdefinite geometrical relationships to each other, forming a kind of scaffoldingcalled a crystalline lattice. On the basis of its chemistry and the arrangementof its atoms, a crystal falls into one of 32 classes; these in turn are groupedinto seven systems according to the relationships of their axes. Differencesin the physical properties of crystals sometimes determine the use to whichthey can be put in industry. In crystals, however, a collections of atomscalled the Unit Cell is repeated in exactly the same arrangement over andover throughout the entire material. Because of this repetitive nature, crystalscan take on strange and interesting looking forms natura lly. When crystals aregrown there is a separating of all the building block molecules into individualunits in water and letting them fall naturally into their appropriate place in therepetitive structure as the water evaporates.