concept 8.2: the free energy change of a reaction tells us whether or not the reaction occurs spontaneously

what is free energy

the portion of a systems energy that can do work when temperature and pressure are uniform throughout the system or in a living cell

what does free energy measure

measure of a systems instability or its tendency to change to a more stable stress

what is equilibrium

a state of maximum stability

ΔG

change in free energy

ΔH

change in enthalpy (total energy)

ΔS

change in entropy

T

temperature in Kelvin (K)

What can delta G for a process be used to determine

Delta G can determine whether it is spontaneous or not

delta G is negative for

spontaneous processes

delta G is zero or positive for

non- spontaneous processes

what does delta G represent

the difference between free energy of the final state and free energy of the initial state

what is the equation used to find delta G

ΔG = Gfinal state – Ginitial state

what does it mean for a reaction to have a negative delta G

it means the system loses free energy and becomes more stable

what does it mean if a reaction has a positive delta g

the system gains free energy and becomes more unstable

what does more free energy mean

higher G

less stable

greater work capacity

what does less free energy

lower G

more stable

less work capacity

what all happens in a spontaneous change

the free energy of the system decreases

the system becomes more stable

the released free energy can be harnessed to do work

exergonic

energy outward

proceeds with a net release of free energy to the surroundings

endergonic

energy inward

absorbs free energy from the surroundings

what does the hydrolysis of maltose produce

2 glucose molecules

is the hydrolysis of maltose spontaneous or non spontaneous

maltose hydrolysis is spontaneous

is delta G (+) or (-) in exergonic reaction

delta G is negative

is exergonic spontaneous or nonspontaneous

exergonic reactions are spontaneous

what does it mean to be spontaneous

a reaction is energetically favorable

is hydrolysis catabolic or anabolic

hydrolysis is catabolic

is dehydration catabolic or anabolic

dehydration reaction is anabolic

anabolic: nonspontaneous/spontaneous OR endergonic/ exergonic

anabolic is non spontaneous and endergonic

Catabolic: nonspontaneous/spontaneous OR endergonic/ exergonic

catabolic reaction is spontaneous and exergonic

what occurs when reactions occur in a closed system

they eventually reach equilibrium and stop doing work

what is a defining feature of life

metabolism is never at equilibrium

what is an example of catabolic pathways

closed and open hydroelectric systems

are the chemical reactions of metabolisms reversible

the chemical reactions of metabolisms are reversible but never reach equilibrium