Members of the Summer Bridge program preparing to start a lab on "engineering a plastics separation". Photo courtesy of Jade Fostvedt.
An introductory cohort of 13 incoming first-year chemistry students were invited to take part in a new summer chemistry course, Preparation for Chemistry for College of Chemistry Majors. This six-week, rapid-paced lab and lecture course is part of the UC Berkeley Summer Bridge Program designed to help aspiring chemistry students who were unable to pursue advanced chemistry coursework in high school. The College gratefully acknowledges the Summer Bridge program sponsorship from alumni Dr. David Gee (B.S. '76, Chem; MD '80, UCSF; Member Board of Trustees, UC Berkeley) & Dr. David K. Lieu, (B.S. '75, ChemE; MD '79, UC Irvine; MBA '99).
With COVID-19 vaccination rates rising and case numbers falling, the College was able to invite students to participate in the course in person – the first College of Chemistry course to be offered in person since the advent of the pandemic. Students arrived on campus in late June, moved into the dorms, and began attending lectures in Tan Hall on July 6th. The new course is being taught by fifth-year chemistry graduate student Jade Fostvedt, with Prof. Anne Baranger, Associate Dean of Diversity, Equity, and Inclusion, serving as the faculty advisor. Fifth-year chemistry graduate student Katie Blackford is serving as the lab instructor for the course. The teaching team is rounded out by undergraduate peer tutor Ariel Wang, a rising junior chemical biology major.
"Chem 196/196L has helped me relearn concepts in chemistry and has definitely prepared me for Chem 4A. Also, it's nice to have a group of people that you already know and can study with in the fall semester." -- Xavier (Xavi) Albors:
Incoming freshmen Xavier Albors and Tony de Leon in the lab. Photo courtesy of Jade Fostvedt.
The overarching goals for this course are to warmly welcome the Summer Bridge students into the College community, familiarize students with laboratory techniques and etiquette, review chemistry content knowledge, and promote good study habits. To these ends, the Summer Bridge chemistry students are immersed in chemistry five days a week for six weeks. Each week, they attend four hours of lecture, participate in two hours of group problem solving sessions, carry out a three-hour laboratory experiment, and hear research talks from UC Berkeley professors, graduate students, and undergraduate student researchers during the Friday Community Sessions. Topics covered in lecture include models of atoms, chemical bonding, statistics, quantitative analysis, stoichiometry, acid-base chemistry, thermochemistry, and equilibrium. Positive study habits are promoted through explicit lessons on metacognitive problem-solving strategies, peer-to-peer teaching, and weekly journaling exercises.
The laboratory experiments designed for this course give students experience in quantitative and qualitative data analyses, independently designing experimental procedures, carrying out precise techniques using analytical equipment, using Microsoft Excel to analyze data, performing acid-base titrations, and writing formal lab reports. Students also have the exciting opportunity to carry out a two-week project in which they learn how to accurately measure the density of liquids and solids, and then use that knowledge to design and carry out a density-based separation of mixed plastics; this experiment is relevant to the separation of plastics that occurs in an industrial-scale plastic recycling facility.
"Without this class I wouldn't have met my instructors or peer tutor, and without them I wouldn't have a clue as to how to pursue my dreams. This summer has been the bees knees!" -- Marcus (Marc) Crittendon
A description of a recent lesson on statistical analysis provides a snapshot of the course
(l to r) Maria Maldonado, Melany Perez, Cynthia Cunha, Liliana (Lili) Rojas, and Sacy Lopez-Flores prepare to weigh Jolly Rogers in a training exercise for the class. Photo courtesy of Jade Fostvedt.
The lesson began at 9:10 AM (Berkeley time!), with Instructor Jade describing several statistics equations at the front of the room. After about 20 minutes of lecture on calculating mean, standard deviation, and confidence intervals, the students are asked to break into small groups for an activity. The students are given an assignment to find the average mass of a Jolly Rancher ⏤ one student’s favorite candy ⏤ by measuring 10 candies on an analytical balance and calculating the average, standard deviation, and 95% confidence interval. Before the students begin, they discuss several variables among themselves: Should the candy wrapper be included in the measurement? Should they keep track of the colors of candies they’re measuring, in case the different flavors have different masses? After deciding to remove the wrappers and keep track of the colors, the students jump into the activity.
The average masses computed by the groups are all over the place, ranging from 5.781 to 6.288 grams per candy. It seems that the Jolly Rancher factory could benefit from stricter quality control. However, by pooling class data in Excel, the students observed that increasing the sample size from 10 to 30 Jolly Ranchers, the average mass was now 5.967 grams per candy – much closer to the reported 6.0 gram mass of a Jolly Rancher!
Students also measured the mass of a cough drop and used the Grubbs test for outliers to prove that this data point did not belong in the Jolly Rancher data set. Overall, this lesson allowed the Summer Bridge students to practice statistical analysis, see for themselves how increasing sample size is related to experimental uncertainty, and work with peers to collect data and answer questions. Importantly, we didn’t increase our sample size too much: at the end of the lesson, there were still some extra Jolly Ranchers left for the students to enjoy.
"Chem 196 has allowed me to revisit my love for chemistry all while challenging me in both lab and lecture. I absolutely love the Friday community discussions set up for the class to engage with fellow chemistry enthusiasts. Each story, research presentation, and person opens up my mind to the infinite possibilities of what I can do in the future. I am extremely grateful for the opportunity to attend a class with instructors that truly care about making a difference in their students' lives in the span of a few weeks and I can't wait to continue falling in love with chemistry as the course progresses!” -- Liliana (Lili) Rojas