Some students have suggested that I should do more about my aging, overcrowded classroom. They think I should raise a complaint, and get people to understand how rooms like mine make it difficult for students to achieve.
Well. I can't say that my students are wrong on that point. Our situation's not that great, I admit.
But this situation is also something that's definitely in my wheelhouse, as this video from the summer of 2020 should show:
In this VIDEO, Mr. Hatfield uses the whiteboard to demonstrate how to calculate the equilibrium constants for strong and weak acids, and also how to rearrange the equilibrium setups to solve for the concentration of products or the original acid's concentration.
This VIDEO contains useful demonstration of titration, the subject of our next set of Lab Activities, as well as models how to evaluate an equilibrium setup of a chemical system involving acids and bases.
This VIDEO contains Mr. Hatfield's notes on the current unit, based on Sections 15.1 and 15.2 of your text.
Topics include: water's polarity, hydrogen bonding, the dissociation of water, properties of acids and bases, indicators and titrations, the pH scale, acid-base definitions, salts and buffer solutions.
Nora Flanagan is a sophomore English teacher in the Chicago public schools system. In this 'TED Talk' delivered last summer at Wrigley Field during that phase of the global pandemic, she identifies some ongoing problems with the public schools there were present before the pandemic.
Much of what Ms. Flanagan describes are also challenges for Fresno public schools, and so her talk is highly-relevant to what we have experienced and continue to experience as teachers, students or parents in the midst of a global pandemic.
She makes four specific recommendations: "We can and we must engage parents, demand equity, support the whole student and rethink assessment."
The full text of Ms. Flanagan's remarks are available on-line, HERE. As your instructor, I want to encourage all of my students to reflect on her remarks, particularly her comments on how we support the whole student, and whether we consider the student's voice:
"IF WE ARE HAVING CONVERSATIONS ABOUT ANY OF THIS, AND NOT AUTHENTICALLY INCLUDING AND EMPOWERING STUDENTS EVERY STEP OF THE WAY, WE'RE NOT HAVING CONVERSATIONS ABOUT ANY OF THIS."
In this VIDEO, Mr. Hatfield demonstrates the use of 'universal indicator solution' , as a means of comparison with the pH indicator strips used in the "pH of Solutions Lab" performed in class between May 5-12.
Unlike the lab, where we simply estimate pH from color changes, in this demonstration Mr. Hatfield goes back and forth, first adding positive charge (an acid), then negative charge (a base).
This is essentially a series of neutralization reactions swinging back and forth around pH 7 (neutral), and similar in concept to the titrations that will be the subject of our next set of Lab Activities.
In a previous lab, Mr. Hatfield walked students through the steps needed to collect data in the 'Heat of Solution' Lab.
In this VIDEO, Mr. Hatfield explains how students will analyze the data from this Lab for two reactions, one exothermic and the other endothermic.
Students will then use Q =mCdT to find the energies (q) for both reactions in Joules, then discuss how those energies can be used to find the enthalpy of reaction, where dH (delta H) = -(q) / mol
In this VIDEO, Bullard High staff shares how students can access different kinds of tutoring support during the spring 2021 semester:
In this VIDEO, Mr. Hatfield walks students through the protocols and procedures of the 'Heat of Solutions' lab, which uses calorimetry to measure temperature changes ('delta T') in water based on chemical reactions involving sodium hydroxide or ammonium chloride:
In this VIDEO, Mr. Hatfield discusses content from sections 9.1 and 9.2 (chemical reactions, chemical equations) and sections 10.1 and 10.2 (balancing equations and stoichiometry):
This graphic, also shared through TEAMS, list important recent topics in the course, including when they were covered in class and referencing relevant pages of the text:
In this VIDEO, Mr. Hatfield demonstrates how to map an equation for a three-step problem (gram to moles, moles to moles, moles to grams) and then produces the setup based on that map to solve for an unknown number of grams:
Many students have still failed to submit the Dilution Lab assigned in Week 6, and tomorrow is the beginning of Week 8. To assist students, Mr. Hatfield has made a VIDEO showing how to do the dilution calculations which are needed in order to use the simulation. This calculation is similar to those taught in class and found in your textbook on pg. 296-297:
Students were provided two Assignments last week to review the skill of balancing equations.
One was a short set (10 problems) of combination, decomposition and combustion reactions given in class on 2/16 or 2/17, called 'Balancing Equations Review'.
The other was a longer group of 15 problems that included single and double replacement reactions, and which asked students to identify the types of reactions as well as balance equations that were not already balanced, called 'Types of Reactions'. This is due on Monday, 2/22.
To assist students in mastering these previously-taught skills, this VIDEO shows Mr. Hatfield solving examples of each type:
In this VIDEO, Mr. Hatfield introduces largely-conceptual material for the completed unit on Solution Chemistry, covering material from sections 7.5, 7.6, 8.1, 8.2, 8.3 and 8.4 in the text, pages 236-298.
Topics covered included: aqueous systems, properties of water, properties of solution, concentration and molarity problems, percent composition, empirical and molecular formulas.
For information focusing on how to solve particular kinds of problems, see the earlier video placed on the class blog, 'Practice Test Problems'.
In this VIDEO, Mr. Hatfield demonstrates the various kinds of calculation problems found on the Practice Test shared with students through their Microsoft Teams channel.
Calculations introduced this semester include percent composition, empirical and molecular formulas (Section 8.3, pg. 280-289) and molarity and dilution problems (Section 8.4, pg. 292-299).
A separate video will be made available to cover the conceptual material presented in this course since the beginning of the semester.
In this VIDEO, Mr. Hatfield reviews the procedures, previously taught in the fall semester, for calculating molar masses with the aid of the periodic table.
Mr. Hatfield then shows how a substance's molar mass and other conversion factors (Avogadro's number, the molar volume) to show students how to interconvert units of mass, volume and number of particles.
Please note that these slides represent the 'direct instruction' part of the first three days of instruction in the spring semester, with new material (on solutions) set to appear on the fourth day of instruction.
Students, last week you reviewed how to convert moles to grams (and vice versa). This was previously covered during the first two weeks of September in the Fall Semester, and as part of that we had a lab activity called 'Combustion of Paraffin'.
In this VIDEO, I showed students how to the calculations required in that lab, which involved molar masses and grams/moles conversions, and this may help you review the concept:
In this VIDEO, Mr. Hatfield illustrates the compound gas law, the ideal gas law and its applications, the limits of the ideal gas law and that law's relationship to kinetic molecular theory (KMT).
In this VIDEO, Mr. Hatfield demonstrates how to use the ideal gas law to solve for unknown variables of pressure, volume, temperature or number of moles.
Using Avogadro's number, the number of moles can be converted into an estimate of the number of particles (atoms or molecules) present in a given sample of a gas.
In this VIDEO, Mr. Hatfield demonstrates the steps for solving problems based on one of three gas laws: Boyle's Law, Charles' Law and Gay-Lussac's Law. In all three examples, students should first write out the four variables, three of which are given and one is unknown. Students will then isolate the unknown by eliminating one or more variables on both sides of the equation to solve.
