Enthalpy
What is enthalpy represented by in a reaction?
delta S
What is entropy a measure of?
Disorder
What main equation is used to find change in Gibbs Free Energy of a reaction/system?
ΔG = ΔH - T ΔS
What does it mean for a function to be a state function?
The path taken does not matter, just the final - initial values
If a reaction is endothermic: ΔH has a __ sign
ΔH: positive
Which reaction will be more likely to occur: one in with the entropy is positive or one in which the entropy is negative?
The one in which the entropy is positive
The entropy and enthalpy of a high temperature reaction are both negative. Is the reaction spontaneous?
The reaction is nonspontaneous
What does calorimetry measure?
The heat flow of a system(s) during a reaction
If a system decreased in enthalpy would it be exothermic or endothermic?
Exothermic, as the change in enthalpy value will be negative
increases
True or false: Gibbs Free Energy is the true predictor of spontaneity?
True
The chemical equation for methanol is: CH3OH(l) + 3/2 O2(g) ---> CO2(g) + 2 H2O(g). Based on the reaction predict the sign of ΔS
ΔS will be positive
True or False: endothermic processes are always nonspontaneous
False - enthalpy isn't a perfect predictor
The entropy of a pure crystalline substance at absolute zero (0 K) is always _____.
0
A reaction reacts at a low temperature of 45℃ and has a ΔH of -81.22 kJ and a ΔS of -175.75 J/K. What is the ΔG for this reaction?
-25.3 kJ
Rank entropy from highest to lowest in relation to the states of matter.
Solid<Liquid<Gas
what units do you use to measure enthalpy?
joules!
.
false!
T or F.... If ΔS is positive for an exothermic reaction, it is spontaneous for all temperatures
true!
CH4(g)+2O2(g)⇌CO2(g)+2H2O(l)
determine whether the ΔS increases or decreases or stays the same at 25 °C