Living organisms require energy to perform functions. They:

Kidney cells: › to transports materials

Digestive tract: › break macromolecules

Heart: › to pump

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Metabolism:

Anabolism:

Catabolism:

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Energy:

Energy can take many forms:mechanical electric currentheat light

All energy can be classified as:-kinetic energy: -potential energy:

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stored energy. › ___________________________________› ___________________________________

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Potential energy stored in chemical bonds can be transferred from one molecule to another by way of electrons.

oxidation: reduction: redox reactions

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Energy of motion› ________________________________________› ________________________________________

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http://www.youtube.com/watch?v=Jnj8mc04r9E

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Study of heat and energy flow within chemical reactions

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First Law of Thermodynamics –

For example:sunlight energy chemical energy

photosynthesis12

Exercise to lose weight› produce heat and you

sweat› heats the air around you.

When you eat a pizza› energy from the

chemical bonds in the bread, cheese, etc. is broken down

› converted into ATP molecules through cellular respiration.

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______________________________________________________________________________

The enthalpy change (ΔH) › amount of heat released or absorbed when

a chemical reaction occurs at a constant pressure.

› ΔH formation = _____________________________

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Reactants:

Activation energy (Ea): Transition state: Products:

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some of the reactant's potential energy is released into the surroundings as heat.

enthalpy of the products is ____________________

energy is _____________ ΔH is ____________

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http://cwx.prenhall.com/petrucci/medialib/media_portfolio/text_images/019_THERMITE.MOV

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Second Law of Thermodynamics:

entropy:

The 2nd Law of Thermodynamics states that entropy is always increasing.

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Free energy:

-denoted by the symbol G (Gibb’s free energy)

enthalpy:

free energy = enthalpy – (entropy x temp.)

G = H - TS24

Chemical reactions can create changes in free energy.

When products contain more free energy than reactants G is positive.

When reactants contain more free energy than products G is negative.

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Chemical reactions can be described by the transfer of energy that occurs:

endergonic reaction:

exergonic reaction:

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Most reactions require some energy to get started.

activation energy:

catalysts:

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C6H12O6 + O2 → CO2 + H2O + Energy (as ATP)           

ΔG = - 2870 kJ/mol of glucose release of energy an increase in entropy This reaction tends to proceed

spontaneously.  

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Photosynthesis Chemical EquationCO2 + H2O + Energy → C6H12O6 + O2         ΔG = + 2870

kJ/mol of glucose

energy is absorbed a decrease in entropy This reaction does not proceed

spontaneously as energy is needed to drive the reaction.    

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ATP = adenosine triphosphate

ATP structure:

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Adenosine Triphosphate (ATP)Adenosine Triphosphate (ATP)

Section 9.1Section 9.1

PP PPAA PP

Mono = One phosphate groupDi = Two phosphate groupsTri = three phosphates groups

Adenosine Triphosphate (ATP)Adenosine Triphosphate (ATP)

Section 9.1Section 9.1

PP PPAA PP

The battery of the cellThe battery of the cell

Section 9.1Section 9.1

When the bond between phosphates is broken:

ATP ADP + Pi

energy is released

ADP = adenosine diphosphatePi = inorganic phosphateThis reaction is reversible.

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Section 1.3, p.68 1, 2 , 5 , 10 , 11

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