thermodynamics
study of energetics of chemical rxns
first law of thermodynamics
- conservation of energy
- energy in universe is constant
second law of thermodynamics
- entropy
- entropy of universe tends to increase
spontaneous rxns tend to ____ the disorder of the universe
increase
favorable rxns are _____ and non-favorable are _____
spontaneous & non-spontaneous
spontaneous rxns occur without _____
addition of net energy
exergonic rxns
spontaneous
endergonic rxns
non-spontaneous
difference between Keq and Q
Keq is ratio of products over reactants at equilibrium, while Q is at any given point
equilibrium
- point where rate of forward & reverse rxns are equal
- concentrations stay the same
addition of a reactant or product causes change in ____
Q
chemical kinetics
- study of rxn rates
- all rxns proceed through an unstable transition state
activation energy
energy required to produce transition state
catalyst
- lowers activation energy w/o changing G
- stabilizes transition state
- not consumed, regenerated
enzymes
- biological catalysts
- kinetic role, not thermodynamic role
photosynthesis
process by which plants store energy from the sun in the bond energy of carbohydrates
plants are ____
photoautotrophs
humans are ____
chemoheterotrophs
ATP is used to ____
drive energetically unfavorable rxns in cells
oxidation
- gain oxygen atoms
- lose hydrogen atoms
- lose electrons
reduction
- lose oxygen atoms
- gain hydrogen atoms
- gain electrons
redox pair
- if one molecule gets reduced, another gets oxidized
- vice versa
catabolism
- break down of molecules
- generally oxidative
anabolism
- build up molecules
- generally reductive
