Please enable JavaScript.
Coggle requires JavaScript to display documents.
Thermodynamics considerations (ATP and cellular energy conversions…
Thermodynamics
considerations
ATP and cellular energy conversions
Zeroth laws of Thermodynamics
First law of Thermodynamics:
the principle of conservation of energy, In any reaction, the total energy in the universe remains the same just in an altered form
Second Law of thermodynamics:
During energy transfer some of the energy becomes unavailable to do work, There is no perpetual motion.
Third law of thermodynamics:
As the temperature approaches absolute zero, the
entropy
of a system approaches a constant minimum.
Entropy is the measure of a system disorder and randomness.
A process will be spontaneous if the disorder is increasing (+entropy)
A process will not be spontaneous if it involves a decrease in disorder, Endergonic (- entropy)
Exergonic reactions
are where energy/ heat is released, ΔG<0 which indicates that the reaction was spontaneous.
Endergonic reactions
absorb energy, ΔG > 0 which makes the reaction non spontanious. these reactions need input of energy.
Coupled reactions:
Two or more reactions in a cell sometimes can be coupled so that thermodynamically unfavorable reactions and favorable reactions are combined to drive the overall process in the favorable direction. The predominant form of coupling is the use of compounds with high energy to drive unfavorable reactions
Gibbs free energy: portion of a system's energy that can perform work when temperature and pressure are constant.
ΔG = ΔH –TΔS
if ΔG < 0 then the process is spontaneous
if ΔG = 0 then the process is in equilibrium
if ΔG > 0 then the process is not spontaneous
Redox reactions
Chemical reactions in which the atoms have their oxidation state changes!
The oxidation number (or the oxidation state) is the charge that an atom in a molecule would possess if the shared electron pairs in each covalent bond were assigned to the more electronegative element in the bond.
Does not equal to the actual charge on an atom!
Ox number +/-sign is always indicated by the number (Na+> +1) Charge +/-sign is always indicated after the number (Na+-> 1+)
OIL: Oxidation Is Loss
RIG: Reduction Is Gain
ΔH = change in enthalpy (change in heat)
TΔS = change in entropy (order of a system)
ΔG= G final state - G Initial state
