All substances posess some degree of disorder because particles are in constant motion, thus
S is always a positive number
2 of 14
Entropy increases during the changes in state that give more randomness, for example
solid (low entropy --> gas (high entropy)
3 of 14
The more disorder there is in the system, the
Higher the entropy
4 of 14
Entropy ______ when a solid lattice dissolves
Increases
5 of 14
In a reaction where there is an increase in the number of gaseous molecules, entropy
Increases
6 of 14
The standard entropy S, of a substance is
The entropy content of one mole of the substance under standard conditions
7 of 14
The standard entropy change of a reaction can be calculated using the standard entropies of the reactants and products:
ΔSºreaction = ΣSº(products) - ΣSº(reactants)
8 of 14
If a change makes a system more random ΔH is positive, and if a change makes a system more ordered, ΔS is
Negative
9 of 14
Standard entropy change of reaction, ΔSº, is
The entropy change that accompanies a reaction in the molar quantities as expressed in a chemical equation under standard conditions, all in standard states
10 of 14
The free energy change ΔG is
The balance between enthalpy, entropy, and temperature for a process: ΔG = ΔH - TΔS
11 of 14
For an endothermic reaction to take place spontaneously, ΔS must be positive, and the temperature must be high enough so that
TΔS>ΔH
12 of 14
In calculations concerning ΔG= ΔH - TΔS 1, units must be the same for kJ/J
The units need to be the same, to convert ΔS to kJ K^-1 mol^-1 /1000
13 of 14
In calculations concerning ΔG= ΔH - TΔS entropy is worked out using K
To convert C to K add 273 and the opposite to convert K to C
14 of 14
Other cards in this set
Card 2
Front
All substances posess some degree of disorder because particles are in constant motion, thus
Back
S is always a positive number
Card 3
Front
Entropy increases during the changes in state that give more randomness, for example
Comments
Report