Saturday, October 23, 2010
Fri-Day 1
Physics- we discussed Newton's 2nd and 3rd Laws.
The second law relates the NET FORCE/UNBALANCED FORCE as the cause of the ACCELERATION of an object; how much acceleration that is experienced by the object due to a given force depends on its INERTIA/MASS. Quantitatively, the relationship is
Force (net) = Mass x Acceleration
The third law, which will make more sense when we talk about the law of momentum, is that there is an equal and opposite reaction/force to every action/force AS LONG AS the action reaction pair is NOT ON THE SAME OBJECT i.e. the action/reaction pairs MUST be on two different objects for this law to hold true.
AP Chem- our Gas Unit exam will be given next Wednesday or Friday, depending on class academic performance. When you come to class, immediately take out your notes and review them; have questions prepared, and immediately copy anything that I have written on the board/screen. We must be much more efficient, otherwise our class performance and our class schedule will be of substandard, instead of the assumed excellent quality that is required of this course.
we finished the discussion of the gas laws by explaining that adding another gas to a container will increase total pressure but will NOT affect the collision frequency and force (i.e. partial PRESSURE) of the OTHER gas or gases already in there.
We then derived Graham's Law of Effusion/Diffusion by considering the mathematical formula for KINETIC ENERGY. At a given temperature/average kinetic energy, the greater the molecular mass of a molecule, the slower its average velocity, thus the lower its rate of effusion/diffusion. We then applied the formula to compare the relative rates of effusion of two different gases.
We had a detailed discussion of what CAUSES pressure in a container of a sample of gas. By focusing on the 1. pressure causing collision frequency of the gas particles with the container wall and 2. the pressure causing kinetic energy/force of the collisions, we can explain/reason any of the gas laws.
Check out the animation of the gas laws on Blackboard, as well as the thoroughly written explanations posted in the notes from Friday.
The second law relates the NET FORCE/UNBALANCED FORCE as the cause of the ACCELERATION of an object; how much acceleration that is experienced by the object due to a given force depends on its INERTIA/MASS. Quantitatively, the relationship is
Force (net) = Mass x Acceleration
The third law, which will make more sense when we talk about the law of momentum, is that there is an equal and opposite reaction/force to every action/force AS LONG AS the action reaction pair is NOT ON THE SAME OBJECT i.e. the action/reaction pairs MUST be on two different objects for this law to hold true.
AP Chem- our Gas Unit exam will be given next Wednesday or Friday, depending on class academic performance. When you come to class, immediately take out your notes and review them; have questions prepared, and immediately copy anything that I have written on the board/screen. We must be much more efficient, otherwise our class performance and our class schedule will be of substandard, instead of the assumed excellent quality that is required of this course.
we finished the discussion of the gas laws by explaining that adding another gas to a container will increase total pressure but will NOT affect the collision frequency and force (i.e. partial PRESSURE) of the OTHER gas or gases already in there.
We then derived Graham's Law of Effusion/Diffusion by considering the mathematical formula for KINETIC ENERGY. At a given temperature/average kinetic energy, the greater the molecular mass of a molecule, the slower its average velocity, thus the lower its rate of effusion/diffusion. We then applied the formula to compare the relative rates of effusion of two different gases.
We had a detailed discussion of what CAUSES pressure in a container of a sample of gas. By focusing on the 1. pressure causing collision frequency of the gas particles with the container wall and 2. the pressure causing kinetic energy/force of the collisions, we can explain/reason any of the gas laws.
Check out the animation of the gas laws on Blackboard, as well as the thoroughly written explanations posted in the notes from Friday.
# posted by C @ 5:51 PM 
