Term
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Definition
state function, doesn't matter how you get to the "end," just the difference between the "end" and beginng"
-Delta H
-sum of internal energy within a compound/molecule/system |
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Term
| What is the units for enthalpy? |
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Definition
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Term
| What are examples of enthalpy? |
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Definition
| combustion, bomb calorimetry, phase changes |
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Term
| How is energy of a reaction determined? (4) |
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Definition
bomb calorimeter, Hess's law, bond energies,
using delta H for products and reactants |
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Term
| What does it mean when biologists say that molecules store energy? |
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Definition
| products have lower internal energy when compared to ATP |
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Term
| What is the first and second law of thermo? |
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Definition
1. Energy isn't created or destroyed
2.The process reaction will be spontaneous if the disorder in the universe increases |
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Term
| Explain and give an example of why spontinaity cannot rely on enthalpy only |
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Definition
exothermic=spontaneous
endothermic=not spontaneous
cant be true, because things like ice melting, and sugar dissolving in water requries heat or energy, and are therefore endothermic, but occur SPONTANEOUSLY |
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Term
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Definition
kj/mol
vs
heat j or kj
how much we are burning relative to mass
m(H) |
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Term
| A change in entropy from boiling pentane is.. |
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Definition
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Term
a change in entropy from crystallizing a liquid is..
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Definition
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Term
| What is the third law of thermodynamics |
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Definition
| the entropy of a perfect crystal at 0 k is 0 |
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Term
| What is gibbs free energy? |
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Definition
| the amount of "free energy" provided by a rxn |
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Term
| If rxn is endothermic and products are less disordered, than the reaction is |
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Definition
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Term
| if the rxn is exothermic and products are less disordered, than the rxn is |
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Definition
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Term
| what are the ways to determine delta G (3) |
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Definition
1. delta H minus T(delta S)
2. sum of Delta G prod - sum of Delta G reac
3. Hess's law w G values for known rxns |
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Term
| what are the physical properties of gases |
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Definition
1. Occupy the space in which they are contained
2.have the most relative KE
3. much less dense than liqu/solids
4. much more compressible than liqu/solids |
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Term
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Definition
| Force as a result of the molecules colliding with the "walls of their container" |
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
-half filled atomic (s,p,d, hybrid) orbitals overlap=a bond
-good at giving an idea of type and location of bonds
-good at overall shape of molecule quick model
-not good for "ionic" bonding
-not good for partial charges or mobile electrons |
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Term
| describe molecular orbital theory |
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Definition
-summation of atomic orbitals
-# of orbitals (atomics)= # of orbitals (molecular)
-determines the molecular structure by treating the electrons as moving throughout orbitals
-identifies energy levels of rxns
-can predict the existence of molecules
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