CHEM 001 Lecture Notes - Lecture 29: Dynamic Equilibrium, Exothermic Process, Vaporization

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skywildebeest596

13 Aug 2020

School

College of The Sequoias

Department

Chemistry (CHEM)

Course

CHEM 001

Professor

Rodriguez

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Document Summary

The old definition of a calories (new is 4. 184 j) A. calorimeter: device that measures energy change. Reaction takes place with open top at atmospheric pressure thus expanding gases cannot be contained = constant pressure. C. recall: at constant pressure: q = h. D. thus from q = mc t; q = change in heat. Used to measure the change in internal energy of a reaction, at. C. the steel vessel heats up the water around it . D. thus from q = mc t; q = change in internal energy. 10 c and add heat: molecules vibrate and temperature rises. 0 c: temperature stops rising with additional heat because bonds are breaking and ice is melting. 0 c+: temperature starts rising with additional heat as molecules. 100 c: temperature stops rising with additional heat because bonds are breaking and water is boiling. 100 c+: temperature starts rising with additional heat as molecules vibrate vibrate.

Related Questions

Calorimetry is a method used to measure changes inenthalpy, or heat, that occur during chemical processes. Two commoncalorimeters are constant-pressure calorimeters and constant-volume(or "bomb") calorimeters. Bomb calorimeters are used to measurecombustion and other gas-producing reactions, in which the reactionis observed in a strong, sealed vessel. A simple constant-pressurecalorimeter can be made from a foam coffee cup and a thermometer,in which energy changes in a reaction are observed via the changein temperature of the solution in the cup. The idea behindcalorimeters is that if they are sufficiently insulated from theoutside environment, any energy gained or lost in the chemicalreaction will be directly observable as a temperature and/orpressure change in the calorimeter.