Monday, October 27, 2008
Mon-Day 2
AP Chem: we will finish our hypochorite (bleach) titration tomorrow 3rd Period in ROOM 307!
If you show up there first, I'll know that you did your daily hw reading.
:)
Today, we reviewed all of the material that we have covered in the Ch.3 and Ch.4 moles and stoichiometry unit. We also discussed common errors in these problems and in dilution/molarity problems.
We then finished Friday's limiting reagent solution stoichiometry problem. Some of you are not practicing nearly enough as you are unfamiliar with the meaning of the coefficients in a chemical equation. The ONLY purpose of the coefficient is to tell you the RATIO of MOLES of a given reactant used up to MOLES of another reactant used up OR MOLES of a given product formed. THAT IS ALL!!! NEVER EVER use a coefficient from ANY balance equation to compute a molar mass of an element or a compound. NEVER!
Furthermore, in EVERY stoichiometry problem, the question MUST give you ALL pertinent and useful information. In fact, the data in the question DICTATES how you must solve the problem so LABEL ( M or V or n or grams reactant) the data RIGHT in the question and then, as you have seen, we practically always:
1. convert to ACTUAL moles of substance
2. plug that into the BALANCED equation to determine limiting and excess reactants
3. use the limiting reactant MOLE RATIO to determine ACTUAL moles of product(s) formed and MOLES of other reactant(s) used up.
4. convert MOLES to grams or (given molarity) volumes of any and all substances!
That is it.
Bio 6- we completed our detailed pictures of DNA replication that takes place during the S part of interphase. We related our picture to what is occurring on the chromosome: the DNA replication LITERALLY forms a second identical "sister chromatid" making the chromosome go from a single-chromatid chromosome to a double-chromatid chromosome. Without this important formation of identical sister chromatids, mitosis could NOT occur because the daughter cells would not have the same number and types of chromosomes as the original cell due to the lack of DNA.
We then discussed the importance of the Watson-Crick model/picture of DNA, showing how it explained/accounted for the ability of cells to reproduce identical cells with the same genetic information and also how DNA could code information that is translated into the specific amino acid sequence of all of the proteins that give an organism its specific traits and characteristics.
We began a DNA and mitosis worksheet that we will finish tomorrow.
Bio 7/8- Bio 6- we completed our detailed pictures of DNA replication that takes place during the S part of interphase. We related our picture to what is occurring on the chromosome: the DNA replication LITERALLY forms a second identical "sister chromatid" making the chromosome go from a single-chromatid chromosome to a double-chromatid chromosome. Without this important formation of identical sister chromatids, mitosis could NOT occur because the daughter cells would not have the same number and types of chromosomes as the original cell due to the lack of DNA.
We then discussed the importance of the Watson-Crick model/picture of DNA, showing how it explained/accounted for the ability of cells to reproduce identical cells with the same genetic information and also how DNA could code information that is translated into the specific amino acid sequence of all of the proteins that give an organism its specific traits and characteristics.
We almost completed our lab discussion on the NY State osmosis lab; we will do so on Wednesday before we begin our next lab.
If you show up there first, I'll know that you did your daily hw reading.
:)
Today, we reviewed all of the material that we have covered in the Ch.3 and Ch.4 moles and stoichiometry unit. We also discussed common errors in these problems and in dilution/molarity problems.
We then finished Friday's limiting reagent solution stoichiometry problem. Some of you are not practicing nearly enough as you are unfamiliar with the meaning of the coefficients in a chemical equation. The ONLY purpose of the coefficient is to tell you the RATIO of MOLES of a given reactant used up to MOLES of another reactant used up OR MOLES of a given product formed. THAT IS ALL!!! NEVER EVER use a coefficient from ANY balance equation to compute a molar mass of an element or a compound. NEVER!
Furthermore, in EVERY stoichiometry problem, the question MUST give you ALL pertinent and useful information. In fact, the data in the question DICTATES how you must solve the problem so LABEL ( M or V or n or grams reactant) the data RIGHT in the question and then, as you have seen, we practically always:
1. convert to ACTUAL moles of substance
2. plug that into the BALANCED equation to determine limiting and excess reactants
3. use the limiting reactant MOLE RATIO to determine ACTUAL moles of product(s) formed and MOLES of other reactant(s) used up.
4. convert MOLES to grams or (given molarity) volumes of any and all substances!
That is it.
Bio 6- we completed our detailed pictures of DNA replication that takes place during the S part of interphase. We related our picture to what is occurring on the chromosome: the DNA replication LITERALLY forms a second identical "sister chromatid" making the chromosome go from a single-chromatid chromosome to a double-chromatid chromosome. Without this important formation of identical sister chromatids, mitosis could NOT occur because the daughter cells would not have the same number and types of chromosomes as the original cell due to the lack of DNA.
We then discussed the importance of the Watson-Crick model/picture of DNA, showing how it explained/accounted for the ability of cells to reproduce identical cells with the same genetic information and also how DNA could code information that is translated into the specific amino acid sequence of all of the proteins that give an organism its specific traits and characteristics.
We began a DNA and mitosis worksheet that we will finish tomorrow.
Bio 7/8- Bio 6- we completed our detailed pictures of DNA replication that takes place during the S part of interphase. We related our picture to what is occurring on the chromosome: the DNA replication LITERALLY forms a second identical "sister chromatid" making the chromosome go from a single-chromatid chromosome to a double-chromatid chromosome. Without this important formation of identical sister chromatids, mitosis could NOT occur because the daughter cells would not have the same number and types of chromosomes as the original cell due to the lack of DNA.
We then discussed the importance of the Watson-Crick model/picture of DNA, showing how it explained/accounted for the ability of cells to reproduce identical cells with the same genetic information and also how DNA could code information that is translated into the specific amino acid sequence of all of the proteins that give an organism its specific traits and characteristics.
We almost completed our lab discussion on the NY State osmosis lab; we will do so on Wednesday before we begin our next lab.
# posted by C @ 1:28 PM 
