Télécharger Thermochemistry sur PC

Thermochemistry Sur iTunes

Calculate the heat capacity of the calorimeter in J/°C, if final temperature of the water is 39.7 °C.  cette application helps in evaluation of enthalpy or heat release/absorption of a system undergoing numerous temperature changes and phase transitions.  Calorimetry section provides means for evaluation of the heat capacity of calorimeter and for finding equilibrium temperature of mixed system.  The calculations take advantage of known values of heat capacity at constant pressure (Cp) and molar or per gram enthalpy of phase transition.  Backward arrow button sets missing temperature or heat capacity of one of the components.  Important! Water didn’t cross temperature of phase transition – vaporization; otherwise calculation would be more complex.  Problem 3: Determine the final temperature when 10.0 g of aluminum at 130.0 °C mixes with 200.0 grams of water at 25.0 °C.  Problem 2: Determine the heat capacity of a coffee-cup calorimeter.  Negative enthalpy points to exothermic process – heat release, while positive one to endothermic - heat absorption.  Please note the starting temperature of the metal is above the boiling point of water.  Enthalpy values show heat flow for each component.  Forward arrow button sets the final temperature of the mixture.  In reality, the sample may vaporize a tiny amount of water, but we will assume it does not for the purposes of the calculation.  Amount of compound can be defined in grams or moles, in a way that Cp and enthalpy units would match.  During calibration 100.0 g of water at 58.5 °C has been added to 100.0 g of water, already in the calorimeter, at 22.8 °C.  Problem 1: Calculate the amount of energy required to change 100.0 g of ice at -15.0 °C to steam at 125.0 °C.  1) The colder water will warm up and the warmer metal will cool down.  The whole mixture will equilibrate up at the same temperature.  App provides enthalpy values for each step.  Example: Calculate the Gibbs free energy for the following reaction at 25 °C.  ΔGf° = 0; for elements in their standard state by definition.  Special attention should be paid for units’ consistency.  °C and K are interchangeable.