Wednesday, April 1, 2009
Wednes-Day 2
AP Chem- emphasized the meaning of the little "bubble" that appears next to delta H, G, or S when STANDARD STATES must be kept for the measurement. Therefore, a delta G STANDARD (with the bubble) means that all gaseous reactants and products MUST be maintained/kept at ONE atm pressure.
We saw how to calculate the standard change in FREE ENERGY for a reaction EITHER from standard free energy of FORMATION values, with which we apply a HESS'S LAW type calculation OR, given delta H of formation values AND absolute enthalpy values, we can use Gibbs equation.
We did a delta G reaction calculation and then, ASSUMING that delta H and DELTA S values do not vary much with temperature ( ABSOLUTE ENTROPY, S, CERTAINLY varies GREATLY with temp BUT DELTA S does not!), we calculated the temperature at which a reaction just becomes spontaneous (or nonspontaneous) i.e. the temperature at which the reaction is at EQUILIBRIUM.
Bio 6- did a simulation lab that explains the process of gel electrophoresis: this technique is used to separate a mixture of different size DNA strands that have been cut by restriction enzymes; the technique is also used to separate a mixture of different size polypeptides/proteins.
Here is a link to that genetics site.
Bio 7/8- We discussed the various types of chromosomal mutations and how to use a karyotype in order to spot the result of a nondisjunction mutation that results in a person with one more or one less chromosome.
We then did a simulation lab that explains the process of gel electrophoresis: this technique is used to separate a mixture of different size DNA strands that have been cut by restriction enzymes; the technique is also used to separate a mixture of different size polypeptides/proteins.
Here is a link to that genetics site.
We saw how to calculate the standard change in FREE ENERGY for a reaction EITHER from standard free energy of FORMATION values, with which we apply a HESS'S LAW type calculation OR, given delta H of formation values AND absolute enthalpy values, we can use Gibbs equation.
We did a delta G reaction calculation and then, ASSUMING that delta H and DELTA S values do not vary much with temperature ( ABSOLUTE ENTROPY, S, CERTAINLY varies GREATLY with temp BUT DELTA S does not!), we calculated the temperature at which a reaction just becomes spontaneous (or nonspontaneous) i.e. the temperature at which the reaction is at EQUILIBRIUM.
Bio 6- did a simulation lab that explains the process of gel electrophoresis: this technique is used to separate a mixture of different size DNA strands that have been cut by restriction enzymes; the technique is also used to separate a mixture of different size polypeptides/proteins.
Here is a link to that genetics site.
Bio 7/8- We discussed the various types of chromosomal mutations and how to use a karyotype in order to spot the result of a nondisjunction mutation that results in a person with one more or one less chromosome.
We then did a simulation lab that explains the process of gel electrophoresis: this technique is used to separate a mixture of different size DNA strands that have been cut by restriction enzymes; the technique is also used to separate a mixture of different size polypeptides/proteins.
Here is a link to that genetics site.
# posted by C @ 2:16 PM 
