Ch 7: Thermochemistry Flashcards Preview

General Chemistry > Ch 7: Thermochemistry > Flashcards

Flashcards in Ch 7: Thermochemistry Deck (23):
1

isolated system

exchange neither matter nor energy with the environment

2

closed system

exchange energy but not matter with the environment

3

open system

exchange both energy and matter with the environment

4

isothermal

processes occur at a constant temperature

5

adiabatic

processes exchange no heat with the environment

6

isobaric

processes occur at a constant rate

7

isovolumetric (isochoric)

processes occur at a constant volume

8

state functions

describe physical properties of an equilibrium state; pathway independent

pressure, density, temp, volume, enthalpy, internal energy, gibbs free energy, entropy

under PRESSURE feeling DENSE, i want HUGS and TV

9

standard conditions

298K
1 atm
1 M conc

10

standard state of an element is prevalent under standard conditions

stand enthalpy, stand entropy, stand free energy

11

phase changes exist at

characteristic pressure and temperatures

12

fusion is ___ and freezing is ___ occur btw solid and liquid phases

melting

crystallization or solidification

13

vaporization _____ and condensation occur btw liq and gas

evaporation or boiling

14

occur at boundary btw solid and gas phase

sublimation and deposition

15

at temps above the _____ liq and gas phases are indistinguishable

critical point

16

at the ____ all 3 phases of matter exist in equilibrium

triple point

17

temperature

scaled measure of average kinetic energy of a substance

18

heat

transfer of energy that results from difference of temperature between two substances

19

enthalpy

measure of the potential energy of a system found in intermolecular attractions and chemical bonds

20

hess's law

states that the total change in potential energy of a system is equal to the changes of potential energies of the individual steps of the process

21

can be calculated using heat of formation, heats of combustion, or bond dissociation energies

enthalpy

22

entropy

often thought of as disorder, measure of degree to which energy has been spread throughout a system or between a system and its surroundings

ratio of heat transferred per mole per unit kelvin

maximized at equilibrium

23

gibbs free energy

derived from both enthalpy and entropy and determines if process is spontaneous or non-spontaneous

depends on temperature; temp dep processes change btw spontaneous and nonspontaneous depending on the temp