FSHN 101 Lecture Notes - Lecture 12: Amblimation, Triple Point, Hydrogen Bond

• School: University of Illinois
• Department: Food Science and Human Nutrition
• Course: FSHN 101
• Professor: Bohn Dawn

Document Summary

Lecture 12: water: its role in life and in foods. H20= most abundant and unique chemicals on earth. Composed of o2 and 2 hydrogen atoms joined together by polar covalent bonds (sharing) Oxygen = electronegative(not sharing equally-- electrons are closer to it) elements, so there is a partial positive charge on each h atom and a partial negative charge on the oxygen atom. The water molecule has three types of motions: depends on temp/ pressure. Can do all 3 motions @ once. Solid (ice): 2nd closest together molecules, positions of molecules are fixed, never stop vibrating. Liquid: molecules are closest together, move in clusters, very close together, translate, rotate, vibrate. Vapor (gas): empty space between molecules, moving 640 m/s, translate, rotate, rotate. Triple point: . 0099 temp , . 006 atm pressure, 374 degrees celsius. If pressure remains constant while temp increases, the additional energy allows molecules to become more mobile. If temp = constant, and pressure increases it becomes less mobile.