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Flashcards in Chapter 7- Deck (22):
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Enthalpy

A function representing heat under conditions of constant pressure

1

Change in enthalpy

Delta H: it is the energy difference between the products and the reactants of a chemical rxn

Delta H < 0 exothermic
Delta H > 0 endothermic

2

Which is spontaneous, exo or endo?

Exothermic

3

Entropy

The measure of the statistical distribution of energy in a system

Gases>liquid>solid

4

Gibbs free energy (G)

A function which considers both the entropy and enthalpy of a system

5

Thermodynamics

The study of energy, work, and heat

6

System

Contains the process under study

7

Surroundings

The universe
Energy can be gained or lost by the system from the surroundings

8

1st law of thermodynamics

Energy cannot be created or destroyed

9

2nd Law of Thermodynamics

The universe spontaneously tends toward increasing entropy

10

3rd Law of Thermodynamics

The entropy of a pure crystal at absolute zero is 0

11

Exothermic Rxn

Releases energy to it's surroundings

12

Endothermic Rxn

Absorbs energy from it's surroundings

13

Ions with the same charge

Repel

14

Rate generally increases as the what increases?

Concentration and temperature

15

Calorimetry

The measurement of heat energy changes in a chemical Rxn

16

Specific Heat (Cs)

The amount if heat (calories or joules) needed to raise the temperature of 1 gram of the substance 1 degree Celsius

17

How do you find the amount of heat that is absorbed or released?

Q = Ms x deltaT x Cs

Ms is grams
Delta T is temp
Cs is specific heat

18

Fuel value

The amount of energy per gram of food

19

1 Cal =

1 kilocalorie or 1000 Cal

20

Chemical Kinetics

The study of rate of chemical rxns

21

Mechanism

A step by step description of how reactants become products