13.2 Flashcards
are the products or reactants more energetically stable in an exothermic reaction
the products are more energetically stable as they have less energy than the reactants
what makes a reaction spontaneous
the reaction takes place at room temperature without any continuous intervention
define entropy
a property of matter that is associated with the degree of disorder of the particles
what happens to entropy if the level of disorder increases
entropy increases
is entropy greater in solids or gases and why
gases because in a gas the molecules are free to move randomly
what is the entropy change of the system
species taking part in the reaction
what is the entropy change of the surroundings
everything else, often the reaction vessel
what is the equation for total entropy change
Stotal = #Ssystem + #Ssurroundings
for a reaction to be spontaneous total entropy (#Stotal) must be….
positive
how do you calculate #Ssystem
Ssystem = £#Sproducts - £#Sreactants
what is the equation for #Ssurroundings
Ssurroundings = - #H/T
is #H positive or negative in exothermic reactions
negative
is #H positive or negative in endothermic reactions
positive
if #H is negative then #Ssurroundings will be….
positive
if #H is positive then #Ssurroundings will be….
negative
