Tuesday, December 4, 2007
Tues-Day 1
Bio- we focused on the other anaerobic respiration/alcoholic fermentation. This process occurs in yeast and certain bacteria. As in lactic acid fermentation, glucose is first broken down via glycolysis into 2 pyruvic acid molecules causing a net production of 2ATP and 2 NADH molecules. However, in alcohol fermentation, ETHANOL, a 2-carbon molecule is formed. Therefore, the pyruvic acid molecules have to be further broken to a 2-carbon molecule (acetaldehyde) and carbon dioxide. REMEMBER, whenever alcohol is produced via fermentation, so is carbon dioxide; you can remember this by picturing BEER or CHAMPAGNE (the bubbles are carbon dioxide!) both of which are made via alcoholic fermentation by yeast or bacteria!
Recall that NO carbon dioxide is made in lactic acid fermentation because lactic acid is a 3-carbon molecule that is not broken down further.
We then discussed cellular respiration that uses oxygen: aerobic respiration. This process, by completely breaking down glucose to carbon dioxide and water, transfers much more energy from the bonds of glucose to the bonds of ATP molecules; in fact, instead of just 2 ATP, a total of 36 ATP molecules are formed per molecule of glucose aerobically respired. Aerobic respiration involves sending the pyruvic acid molecules (formed via the glycolysis of glucose in the cytoplasm) to the MITOCHONDRIA where they will be broken down in the Krebs/Citric Acid Cycle and then, using oxygen, more ATP will be produced via the ELECTRON TRANSPORT CHAIN of proteins that line the inner mitochondrial membrane.
We then did a lab that showed the increased rate of cellular respiration that must occur when your cells need more energy due to increased exercise. This increased respiration rate shows up as an increase in the production of carbon dioxide, which is one of the main products of respiration.
We measured the amount of carbon dioxide breathed into a solution of water and acid-base indicator by neutralizing the carbonic acid (formed when CO2 reacts with water) with a base. We saw that the carbonic acid was neutralized when the acid-base indicator turned pink as the solution became basic.
Chem 7- we discussed "nuclear physics" today; we focused on the four types of emanations that come from unstable isotopes called radioisotopes. The radioisotopes and possible emitted particles are listed on Tables N and O on the Reference Tables. The positive particles that can be emitted from unstable nuclei are alpha particles ( +2 charge and ~ 4 amu mass) or positrons
(+1 charge and very small mass ~ 1/1836 amu). The negative particles that emanate from some unstable nuclei are electrons/beta (-) particles. Some unstable nuclides emit high energy GAMMA photons.
We then drew out the Bohr and QM electron configurations of various cations and anions. ONLY METALS lose electrons to form cations. Metals lose their valence electrons and become POSITIVE cations with a noble gas electron configuration. ONLY NONMETALS gain electrons to form negative anions with a noble gas configuration and an OCTET (eight) of valence electrons (except for H).
Good luck on Wednesday's exam!
Chem 8/9- we discussed "nuclear physics" today; we focused on the four types of emanations that come from unstable isotopes called radioisotopes. The radioisotopes and possible emitted particles are listed on Tables N and O on the Reference Tables. The positive particles that can be emitted from unstable nuclei are alpha particles ( +2 charge and ~ 4 amu mass) or positrons
(+1 charge and very small mass ~ 1/1836 amu). The negative particles that emanate from some unstable nuclei are electrons/beta (-) particles. Some unstable nuclides emit high energy GAMMA photons.
We then drew out the Bohr and QM electron configurations of various cations and anions. ONLY METALS lose electrons to form cations. Metals lose their valence electrons and become POSITIVE cations with a noble gas electron configuration. ONLY NONMETALS gain electrons to form negative anions with a noble gas configuration and an OCTET (eight) of valence electrons (except for H).
We then discussed our flame test and emission spectra exam. In order to detect the elements in an unknown mixture's spectrum, ALWAYS look at the KNOWN spectra first and check that EACH AND EVERY emission line from the KNOWN is also in the UNKNOWN. If that is not the case, then the KNOWN element is NOT in the UNKNOWN mixture of elements.
We reviewed electron transitions, excited state electrons, and ground state electrons. Remember, PHOTONS (specific-energy packets) can ONLY be formed when an electron LOSES energy as it undergoes a TRANSITION from a higher energy level to a lower energy level. That energy lost is TRANSFORMED into a PHOTON of energy!
Good luck on Wednesday's exam!
Recall that NO carbon dioxide is made in lactic acid fermentation because lactic acid is a 3-carbon molecule that is not broken down further.
We then discussed cellular respiration that uses oxygen: aerobic respiration. This process, by completely breaking down glucose to carbon dioxide and water, transfers much more energy from the bonds of glucose to the bonds of ATP molecules; in fact, instead of just 2 ATP, a total of 36 ATP molecules are formed per molecule of glucose aerobically respired. Aerobic respiration involves sending the pyruvic acid molecules (formed via the glycolysis of glucose in the cytoplasm) to the MITOCHONDRIA where they will be broken down in the Krebs/Citric Acid Cycle and then, using oxygen, more ATP will be produced via the ELECTRON TRANSPORT CHAIN of proteins that line the inner mitochondrial membrane.
We then did a lab that showed the increased rate of cellular respiration that must occur when your cells need more energy due to increased exercise. This increased respiration rate shows up as an increase in the production of carbon dioxide, which is one of the main products of respiration.
We measured the amount of carbon dioxide breathed into a solution of water and acid-base indicator by neutralizing the carbonic acid (formed when CO2 reacts with water) with a base. We saw that the carbonic acid was neutralized when the acid-base indicator turned pink as the solution became basic.
Chem 7- we discussed "nuclear physics" today; we focused on the four types of emanations that come from unstable isotopes called radioisotopes. The radioisotopes and possible emitted particles are listed on Tables N and O on the Reference Tables. The positive particles that can be emitted from unstable nuclei are alpha particles ( +2 charge and ~ 4 amu mass) or positrons
(+1 charge and very small mass ~ 1/1836 amu). The negative particles that emanate from some unstable nuclei are electrons/beta (-) particles. Some unstable nuclides emit high energy GAMMA photons.
We then drew out the Bohr and QM electron configurations of various cations and anions. ONLY METALS lose electrons to form cations. Metals lose their valence electrons and become POSITIVE cations with a noble gas electron configuration. ONLY NONMETALS gain electrons to form negative anions with a noble gas configuration and an OCTET (eight) of valence electrons (except for H).
Good luck on Wednesday's exam!
Chem 8/9- we discussed "nuclear physics" today; we focused on the four types of emanations that come from unstable isotopes called radioisotopes. The radioisotopes and possible emitted particles are listed on Tables N and O on the Reference Tables. The positive particles that can be emitted from unstable nuclei are alpha particles ( +2 charge and ~ 4 amu mass) or positrons
(+1 charge and very small mass ~ 1/1836 amu). The negative particles that emanate from some unstable nuclei are electrons/beta (-) particles. Some unstable nuclides emit high energy GAMMA photons.
We then drew out the Bohr and QM electron configurations of various cations and anions. ONLY METALS lose electrons to form cations. Metals lose their valence electrons and become POSITIVE cations with a noble gas electron configuration. ONLY NONMETALS gain electrons to form negative anions with a noble gas configuration and an OCTET (eight) of valence electrons (except for H).
We then discussed our flame test and emission spectra exam. In order to detect the elements in an unknown mixture's spectrum, ALWAYS look at the KNOWN spectra first and check that EACH AND EVERY emission line from the KNOWN is also in the UNKNOWN. If that is not the case, then the KNOWN element is NOT in the UNKNOWN mixture of elements.
We reviewed electron transitions, excited state electrons, and ground state electrons. Remember, PHOTONS (specific-energy packets) can ONLY be formed when an electron LOSES energy as it undergoes a TRANSITION from a higher energy level to a lower energy level. That energy lost is TRANSFORMED into a PHOTON of energy!
Good luck on Wednesday's exam!
# posted by C @ 4:06 PM 
