EARTH 221Introductory Geochemistry
- Units
- 0.50
- Faculty
- Science
- Subject
- Earth Sciences
When it runs
- F24
- W25
- S25
- F25
- W26
- S26
- F26
- W27
- S27
Ran in 4 of the last 7 terms. Winter 2027: scheduled, 2 lecture sections. Spring 2027: schedule not out yet.
Origin, abundance, and geochemistry of elements. Introduction to environmental isotope geochemistry and radiometric dating. Basic aqueous geochemistry: pH, carbonate equilibrium, and common ions in natural waters.
Prerequisites
- Complete 1 of the following
- Must have completed at least 1 of the following:
- Complete all of the following
- Students must be in level 2A or higher
- Enrolled in H-Geological Engineering
Antirequisites
None listed.
Leads to
Winter 2027 sections
| Section | Class | Enrolled | Meets |
|---|---|---|---|
| LEC 001 | 6578 | 0 / 60 | TTh 13:00–14:20 |
| LEC 701 | 2514 | 39 / 9999 | Online or by arrangement |
| TUT 101 | 6579 | 0 / 60 | Th 14:30–16:20 |
Reviewed on UW Flow
68% liked it44% easy69% useful
From 34 ratings and 10 comments on UW Flow. The most helpful comments, quoted as written, without names. Read them all on UW Flow.
I liked this course way more than I thought I would, after taking Chem 120/123 and not enjoying them at all. Where Chem 120/123 would give you a content and tell you to memorize it and leave you behind if you didn't understand, Earth 221 gives a comprehensive review of the Chem material, then shows you how to apply it to geoscience. Exams were incredibly fair, and covered all the content in the course, having all short/long answer questions, rather than having to hedge your bets on what to study for, and none of those awful multiple choice questions where each answer is correct, but one is more correct than the others.
Mar 2022 · liked it · 1 found this helpfulOn UW FlowRemove this
Brians half is good
Sherry ruins the second halfMar 2015 · liked it · 1 found this helpfulOn UW FlowRemove this
This was such a fun course! You touch on so many aspects of the natural sciences and you get to incorporate pretty much a little bit of everything into the course work.
Lectures were pretty fast-paced but If you just show up and try your best to lock-in for the full time to keep up you should be fine. Definitely a lot of content but use the Weekly assignments as a way to review and you should stay on-top of everything, the tutorials are also very helpful for assignments so don't skip those - TAs were both great.
Dr. DelSontro was so kind and funny, she made the lectures interesting and brought energy so you stayed engaged. The Midterm was also very reasonable. Just go to lecture and make…Apr 2026 · liked itOn UW FlowRemove this
Took this with Tonya in Winter 2023. She was very clear with explanations and answers to questions asked in class. Tests were fair, 2-attempt weekly quizzes were great for reinforcing learning.
Nov 2024 · liked itOn UW FlowRemove this
Maddy is one of the worst professors I have ever had in my entire undergrad experience. Awful at explaining and incredibly hard tests as well. If you are taking this class with her, switch out or wait until a different prof is teaching it. The content was completely unorganized and overwhelming.
Jan 2024 · didn’t like itOn UW FlowRemove this
Discussed on r/uwaterloo
5 posts and comments in 5 threads mention EARTH 221, December 2015 to December 2024. Quoted word for word, newest first; each reply sits under the post and the comment that started its branch. Search r/uwaterloo for newer posts.
Fall 2022
syllabussy’s 32 points, 7 comments
u/timetodeathh: “… have it that would also be super slay: - BIOL 130 w/ Holyoak - BIOL 165 - HRM 200 online - EARTH 221 thnx in advance <3 merry holidays uwaterloogang”
Spring 2020
needing advice from Biochem/Chem/Science Majors 5 points, 20 comments
“Heyo I've just accepted to Waterloo's Biochemistry Co-op Program, but after reading the reviews here and looking at the course content I think its way above my skill level, what with the 5 courses …”
u/procrastinating_rn_: “I'm in honours chem and for the first year and a bit we take pretty much the same courses as biochem majors! The only difference is that honours doesn't take any of the biology courses. …”
u/procrastinating_rn_: “… I'm currently doing this with EARTH 221 (Geochemistry 1). It's one of my most work intensive courses this term but I am really enjoying it and it has honestly pushed me to explore some more environmental chemistry based grad programs/career paths! …”
Spring 2019
What is your hardest course of the term? What is your favourite course? 9 points, 17 comments
“title”
[deleted]: “SCI 238 (that’s cause all my courses are super easy but SCI 238 is the most challenging outta the rest) Fav: EARTH 221 / SCI 238 🤣”
Winter 2016
EARTH 221-Study Guide 3 points, 1 comment
u/Howelbert: “Does anyone know of any good study guides for Earth 221? I've been redoing tasks but am having some difficulty remembering how to do certain ones.”
Fall 2015
What are some of the courses that everyone should absolutely avoid? 27 points, 75 comments
“ECON 101 for one.”
u/Ehau: “EARTH 235 : Stratigraphy EARTH 221 : Geochemistry 1”
Check it elsewhere for Fall 2026
- Undergraduate Calendar, 2026–27The official entry
- Requirements for Fall 2026Waterloo’s requisite checker
- Schedule of Classes, Fall 2026Instructors, rooms, live seats
- Quest Class SearchWhere you enrol
- Course outlinesSyllabi from past terms (UW login)
- UW FlowStudent ratings and reviews
- WClassesPast sections back to 2004, and who taught them