the first law of thermodynamics
if a quantity of energy Q is transferred to a system as heat and quantity of energy W is transferred to a system as work
energy can by neither created nor destroyed
energy can be transferred from one system to another as
hear or
work
in biological systems, the energy that is released by the oxidation of nutrients is trnasformed in
heat and work of ATP synthesis
enthalpy of a system is
a modification of the internal energy which automatically taked into account the wotk of expansion
the molar enthalpy of melting
is the change if enthalpy that occures when unit amount of substance of a solid melts
it is that energy that has to be supplied as heat when the melting occures at aconstant pressure
the molar enthalpy of vaporization is
the change of enthalpy that occurs when unit amount of substance of a liquid evaporates
enthalpy of freezing is
the negative of the enthalpy of melting
enthalpy of liquefraction is
the negative of the enthalpy of vaporization
enthalpy of solution is
enthalpy change accompanying dissolution of a salt to give an infinetly dilute solution
enthalpy of combustion is
the enthalpy change accompanying complete combustion of a sample to carbon dioxide and water
Stearic acid has a higher amount of the standart enthalpy of combustion compared to
oleic acid because stearic acid is more reduced (conatins moer H)
Hess law
the overall reaction enthalpy is the sum of the reaction enthalpies of each step into which the reaction may formally be devided
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