Chemistry 221

CH 221Z Announcements

October 5, 2025

Items Due During Week 3:

Section L1: Due in Recitation on Monday, October 6 at 1:10 PM in AC 2501
• The "Density" Lab
• Problem Set #2 (self corrected using the recitation video)
• We will take Seminar Quiz #2 and Quiz #2
• Bring a printed copy of the Hydrogen Spectrum lab to recitation

Section L2: Due in Recitation on Tuesday, October 7 at 8:30 AM in AC 1303
• The "Density" Lab
• Problem Set #2 (self corrected using the recitation video)
• We will take Seminar Quiz #2 and Quiz #2
• Bring a printed copy of the Hydrogen Spectrum lab to recitation

Section L3: Due in Recitation on Wednesday, October 8 at 1:10 PM in AC 2501
• The "Density" Lab
• Problem Set #2 (self corrected using the recitation video)
• We will take Seminar Quiz #2 and Quiz #2
• Bring a printed copy of the Hydrogen Spectrum lab to recitation

Section L4: Due in Recitation on Friday, October 10 at 1:10 PM in AC 2501
• The "Density" Lab
• Problem Set #2 (self corrected using the recitation video)
• We will take Seminar Quiz #2 and Quiz #2
• Bring a printed copy of the Hydrogen Spectrum lab to recitation

ALL SECTIONS:
• Start studying the material in Chapter 2.
• Select a Class Presentation element by Friday, October 10 at 9 AM!
• You can now check your grades for CH 221 by using this link.

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Now that we are beyond the mundane concepts in Chapter 1, we can start looking closer at the composition of the atom. Atoms consist of protons, neutrons and electrons, and we will see how isotopes of elements affect the atomic weight provided on the periodic table. We will also explore the idea of the mole and introduce Avogadro's number (6.022 x 10²³), a number you should memorize. Please contact me if you have any questions, ok?

Here's what is happening in week 3 of CH 221:

• Explore the material in Chapter 2. There are several tools to help you learn the material.... they include:
  • Read Chapter 2 in the textbook
  • Watch the Complete Lectures for Chapter Two here: Part I, Part II
  • Lecture videos for Chapter 2 will be found on YouTube and as a Podcast.
  • Chapter Guide Two (online learning materials for Chapter 2) might be helpful
  • "Mini video lectures" ("Screencasts") can be found in the Videos page for CH 221 under Chapter 2.
  • The Concept Guide for Chapter 2 and other Chapter 2 handouts might prove useful.
• Due: Problem Set #2 which covers problems from Chapter 2.
  • Use this link to get the Fall 2025 version of problem set #2, and use this link to find the recitation video which you can use to self correct your work before turning in to the instructor.
  • Practice Problem Set #2 might be of help while completing problem set #1; answers are included at the end of the practice problem set.
• This Week: Seminar Self Quiz #2 and the (actual) Quiz #2
  • All quizzes (Seminar Self Quizzes and actual Quizzes, as well as midterm exams and finals) are closed book / no notes allowed. You cannot use a cell phone or computer; you can have a dedicated calculator and a periodic table (which I will provide) only.
  • First, take Seminar Self Quiz #2. You will have 20-30 minutes to complete the quiz, and afterwards we will self correct the Quiz as a class before turning it in. If you are late, or do not attend recitation for any reason, your score will be a zero on the Seminar Quiz.
  • After taking the Seminar Self Quiz, you will take the actual Quiz #2. Quiz #2 will take about 30 minutes and consist of several 'show your work' questions. Turn in the quiz when done (I will pass back any corrected work I have for you at this time.)
  • Sample Quiz #2 (answers at the end) might be useful to help you prepare and study.
• Due: The Density Lab.
  • Bring the completed lab with you to recitation.
• Start: The Hydrogen Spectrum Lab.
  • Bring a printed copy of the Hydrogen Spectrum lab with you to lab.
  • Here is a video which shows what the lab will be like, offer hints, etc.
• The deadline for selecting a Class Presentation element is Friday, October 10 at 9 AM.
  • More information about the Class Presentation can be found here.
  • Use this page to select an element, then email me which element you'd like (and include an alternate element or two, just in case)... I'll get back to you quickly.

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Here's a preview of what's happening during Week #4:

• Explore the material in Chapter 3. There are several tools to help you learn the material.... they include:
  • Read Chapter 3 in the textbook
  • Watch the Complete Lectures for Chapter Three here: Part I, Part II
  • Lecture videos for Chapter 3 will be found on YouTube and as a Podcast.
  • Chapter Guide Three (online learning materials for Chapter 3) might be helpful
  • "Mini video lectures" ("Screencasts") can be found in the Videos page for CH 221 under Chapter 3.
  • The Concept Guide for Chapter 3 and other Chapter 3 handouts might prove useful.
• Due: Problem Set #3 which covers problems from Chapter 3.
  • Use this link to get the Fall 2025 version of problem set #3, and use this link to find the recitation video which you can use to self correct your work before turning in to the instructor.
  • Practice Problem Set #3 might be of help while completing problem set #3; answers are included at the end of the document.
• This Week: Seminar Self Quiz #3 and the (actual) Quiz #3
  • All quizzes (Seminar Self Quizzes and actual Quizzes, as well as midterm exams and finals) are closed book / no notes allowed. You cannot use a cell phone or computer; you can have a dedicated calculator and a periodic table (which I will provide) only.
  • First, take Seminar Self Quiz #3. You will have 20-30 minutes to complete the quiz, and afterwards we will self correct the Quiz as a class before turning it in. If you are late, or do not attend recitation for any reason, your score will be a zero on the Seminar Self Quiz.
  • After taking the Seminar Self Quiz, you will take the actual Quiz #3. Quiz #3 will take about 30 minutes and consist of several 'show your work' questions. Turn in the quiz when done (I will pass back any corrected work I have for you at this time.)
  • Sample Quiz #3 (answers at the end) might be useful to help you prepare and study.
• Due The Hydrogen Spectrum lab Lab.
  • Bring the completed lab with you to recitation
• Start: The Chemical Nomenclature Lab.
  • Bring a printed copy of the Chemical Nomenclature lab with you to class.
  • Here is a video which shows what the lab will be like, offer hints, etc.
• Star working on the Rough Draft of your Class Presentation paper.
  • Start working and researching your reserved element for the Rough Draft of your Class Presentation Paper which will be due during the sixth week. More information about the rough draft can be found using this link.

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