what have you completed latley?
This week we took the AP test and I felt pretty confident on it I’m sure u got at least a 4 or 5. For our final in chemistry we tie dyed shirts and mine came out ugly but it was a fun.
What have you learned?
I learned that tie dye is not my thing and that chemistry was worth it.
What are you still struggling with and plan about doing about it.
I’m still struggling with equilibrium and need to retake my quiz. I plan to review in class and learn the material better and hopefully end this year with an A
1. What have you completed recently?
I have taken a moch AP test in chemistry and did surprisingly decent.
2. What have you learned recently?
I have learned about equilibrium of ions in water dealing with dissociation. I also learned about the fight to desegregate the United States in the 60’s.
What are you struggling with and need to work on? I’m still struggling with equilibrium and time usage during the AP test. The best thing to do is go over past notes and master the curriculum down pat.
1. What have you done recently?
I went to state for orchestra we didn’t win anything but it was a great experience. In chemistry we completed a equilibrium lab and notes.
What have you learned recently?
I have learned about equilibrium and equilibrium constants. I also learned that my musical abilities are weak compared to the blessed few.
What are you struggling with and plan to do about it?
I still struggle with the equilibrium math. I plan to review the notes and continue practicing problems and if I still have problems come in for tutoring.
pH is the measure of the concentration of H+ ions in a solution while pOH is the measure of OH- ions in solution. Acids contain the H+ ion and bases contain the OH- ion in the traditional Arrhenius sense. The pH of acids is usually below 7 while the pH of bases is usually above 7. pH and pOH are measured on a scale that is between 1-14 with 7 being neutral meaning that concentration of H+ ion roughly equates to the OH- ion neutralizing each other. pH and pOH are related to H+ and OH- through the math treatment -log(Molarity of substance). This means that the number on the pH and pOH scale is representative of the power of how much of that ion is currently in solution. The larger the pH number the exponentially smaller the amount of hydrogen ions as it is symbolic of a negative exponent.
pH indictators are a tools used to discover the pH of a acid or base. Universal indicator is used to find the pH of an unknown acid or base and works with almost every reaction. This can be done as it is a mix of many indicators. Other indicators are also useful if the pH of a substance is known and they can be used to give off a distinctive color to verify the pH.
If one neutralization reaction occurs at a pH of 5 and another occurs at a pH of 9 different indicators should be used. This allows distinction between the two reactions and with the indicators known to give off color at the certain pH this allows the reaction to be verified that it occured at the proper pH.
Indicators are usually composed of weak acids and bases that interact with the H+ and OH- ions in a system to give off a distinctive color change when their conjugate acid or base forms. Indicators are usually composed of giant complex molecules that are for the most part organic. Indicators are limited however, this is observed as they give a rough estimate of pH, occur at certain pH’s (excluding universal indicator), and can only detect either acid or base. Such as the Alazarine yellow can only detect half the the acids used in the lab while the universal was able to detect all.
Two test tubes, one hot and the other cold, the test tube surrounded by ice contains dinitrogen tetraoxide and the test tube chillin’ in the hot bath contains nitrogen dioxide.
NO2<->N2O4, -58.8 delta H for the production of N2O4. This is a reversible reaction. The production of N2O4 is an exothermic process and the production of NO2 is an endothermic process. Putting test tube in the hot bath added energy to the system favoring the production of NO2 gas giving the orange look. Putting the test tube in an ice bath released energy to the surroundings favoring the production of N2O4 gas giving the colorless look. Both gases are present in both instances but one gas is in higher concentration as it’s being produced at a faster rate. In the instance with the hot test tube the rate of production of NO2 is greater than that of N2O4 hence a greater orange glow, N2O4 is still produced but at a slower rate. This is true for the cold test tube but the reverse with the gases. The N2O4 is at a higher concentration as it is being produced at a higher rate while the NO2 is being produced at a much lower rate. At a neutral temperature neither gas is favored more than the other to be produced as both the delta G’s for their reactions is zero. This is equilibrium when the rates of production equal each other so that products of both gases is relatively the same as the reactants that started the reaction. By changing the temperature of the surroundings and favoring a certain enthalpy change can cause the equilibrium to be disrupted and cause one rate to become higher than the other rate.
Le Chatelier’s principle states that a change to concentration of one of the reactants, pressure of the system, or the temperature of the system will cause a shift in equilibrium to counteract these changes. This principle is observed with the changing rates to counteract the change of temperature of the system.
what have you completed recently?
I have been on my spring vacation all this week. I have read crime and punishment somewhat, read up on WW2, and reviewed chemistry problems.
What have you learned recently?
I learned about equilibrium(barely), about the allies and axis powers, and about Russian literature.
What are you struggling with and plan about doing about it?
I am still struggling with the math of Kinematics and finding the constant. I plan to fix this problem by practicing problems and going over the review UT’s.
1. What have you completed recently.
This week I played a lot of orchestra music, read Oedipus Rex, and played the stock market game.
2. What have you learned recently?
I learned about rates of reactions in chemistry, about FDR in u.s. History, and mind boggling math in pre-calc.
3. What are you struggling with and plan to do about it?
I’m still struggling with the math of rate of reactions. I plan to make this better by doing the homework and practicing how to do the math.