Chapter 5—Energy and States of Matter Energy—the ability to do work Potential energy is stored energy Kinetic is energy in motion 5.2 Measuring Heat Metric unit is joule. 4.18 J = 1 cal. 1 000 cal = 1 kcal = 1 Cal. Calorie with a capital C is the same as the nutritional calorie.

Specific Heat Defn: amount of heat that raises the temperature of 1g of a substance by 1 oC Formula: Specific Heat = Amount of heat Mass x oC DH = m x C x (Tf – Ti)

Changes of State Melting point = changes from solid to liquid Freezing point = same temperature as melting point where liquid becomes solid Heat of fusion = energy during melting needed to separate a solid Sublimation = directly from solid to gas Condensation = from gas to liquid

Intermolecular Forces The greater the intermolecular force, the higher the boiling point London forces (dispersion forces) weakest intermolecular force but increases with molecular weight Dipole-Dipole molecule must be polar, negative end attracts positive end of other molecule Hydrogen bonding strongest intermolecular bond; found in molecules with H, O, N or F.