CHEM 153A Lec 2

Seats

Open, 29 seats left.

321 of 350 enrolled, lecture and all discussions summed.

Read 7 hours ago. The latest refresh is overdue. Seats and instructors may have changed since. Check the registrar before enrolling.

Meets

MTWF 4:00pm-4:50pm

Lecture only. You also attend a discussion, listed below.

Final

Sun 6 Dec, 11:30am to 2:30pm

One exam for the whole class, Los Angeles time.

Read 6 days ago.

Grades

3.31

Predicted GPA

Historical records for LANNAN, RYAN; 5,633 letter grades

dibs has seen this section open 7 times since 18 August. The last time was 25 September.

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25 per account. A lecture watch also covers its discussions. Paused watches still use a slot.

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From the registrar Registrar note

Any student attempting to save or sell a spot for another student is violating Student Conduct Code 102.23d and may be referred to the Office of the Dean of Students. Seats are held for entering students who enroll through New Student Orientation sessions beginning July 2, 2026. New student restrictions will be lifted on September 15, 2026 at 8 a.m. Enrollment is limited to departmental majors on the priority and first enrollment passes. Any student may enroll on the second pass, space permitting. PTE numbers are NOT available; do not contact the instructor for a PTE number. There will be two MANDATORY midterm examinations from 6 to 7:50 p.m. on the following Fridays: October 23 and November 20, 2026.

The new-student hold ended on 15 September.

Restrictions checked 6 days ago and may be outdated. Unwatched sections are rechecked less often than watched sections. Check the registrar before counting on a seat.

Discussions

You enroll in the discussion, not the lecture, so the seat figure above is the sum across all of them and can read open while every discussion you could actually join is full.

12 discussions, 7 open.

Dis 2A
T 9:00am-9:50am

Buechler, E.

Open, 7 seats left.
Dis 2B
T 12:00pm-12:50pm

Nolan, N.

Open, 1 seat left.
Dis 2C
T 1:00pm-1:50pm

Russell, P.

Open, 1 seat left.
Dis 2D
W 9:00am-9:50am

Le, N.

Open, 4 seats left.
Dis 2E
W 11:00am-11:50am

Nolan, N.

Open, 3 seats left.
Dis 2F
W 1:00pm-1:50pm

Buechler, E.

Closed.
Dis 2G
R 9:00am-9:50am

Onwukwe, M.

Open, 6 seats left.
Dis 2H
R 11:00am-11:50am

Onwukwe, M.

Closed.
Dis 2I
R 1:00pm-1:50pm

Morales, B.

Closed.
Dis 2J
F 10:00am-10:50am

Mirabelli, M.I.

Open, 7 seats left.
Dis 2K
F 11:00am-11:50am

Jongert, T.K.

Closed.
Dis 2L
F 2:00pm-2:50pm

Jongert, T.K.

Closed.

Discussion sections, with the seats read in the same sweep as the lecture
Section	Meets	Instructor	Seats
Dis 2A	T 9:00am-9:50am	Buechler, E.	Open, 7 seats left.
Dis 2B	T 12:00pm-12:50pm	Nolan, N.	Open, 1 seat left.
Dis 2C	T 1:00pm-1:50pm	Russell, P.	Open, 1 seat left.
Dis 2D	W 9:00am-9:50am	Le, N.	Open, 4 seats left.
Dis 2E	W 11:00am-11:50am	Nolan, N.	Open, 3 seats left.
Dis 2F	W 1:00pm-1:50pm	Buechler, E.	Closed.
Dis 2G	R 9:00am-9:50am	Onwukwe, M.	Open, 6 seats left.
Dis 2H	R 11:00am-11:50am	Onwukwe, M.	Closed.
Dis 2I	R 1:00pm-1:50pm	Morales, B.	Closed.
Dis 2J	F 10:00am-10:50am	Mirabelli, M.I.	Open, 7 seats left.
Dis 2K	F 11:00am-11:50am	Jongert, T.K.	Closed.
Dis 2L	F 2:00pm-2:50pm	Jongert, T.K.	Closed.

When it meets

Discussion alternatives are shown with the lecture; choose one linked discussion.

Mon

Tue

Wed

Thu

Fri

9am

10am

11am

12pm

1pm

2pm

3pm

4pm

4pm-4:50pm

9am-9:50am

12pm-12:50pm

1pm-1:50pm

4pm-4:50pm

9am-9:50am

11am-11:50am

1pm-1:50pm

4pm-4:50pm

9am-9:50am

11am-11:50am

1pm-1:50pm

10am-10:50am

11am-11:50am

2pm-2:50pm

4pm-4:50pm

Scroll sideways for the whole week. All meeting times are listed below.

Lec 2
MTWF 4:00pm-4:50pm
Dis 2A (alternative)
T 9:00am-9:50am
Dis 2B (alternative)
T 12:00pm-12:50pm
Dis 2C (alternative)
T 1:00pm-1:50pm
Dis 2D (alternative)
W 9:00am-9:50am
Dis 2E (alternative)
W 11:00am-11:50am
Dis 2F (alternative; recorded closed)
W 1:00pm-1:50pm
Dis 2G (alternative)
R 9:00am-9:50am
Dis 2H (alternative; recorded closed)
R 11:00am-11:50am
Dis 2I (alternative; recorded closed)
R 1:00pm-1:50pm
Dis 2J (alternative)
F 10:00am-10:50am
Dis 2K (alternative; recorded closed)
F 11:00am-11:50am
Dis 2L (alternative; recorded closed)
F 2:00pm-2:50pm

Young Hall CS50

Grades

3.31

Predicted GPA

Historical records for LANNAN, RYAN; 5,633 letter grades

Of the 6 other people in the grade record for CHEM 153A, the 2 with the most grades: ELLIS GUARDIOLA, KAT at 3.31 over 1,124 grades and VAZQUEZ-SALAZAR, ALBERTO at 3.61 over 419 grades.

A range: 56%
P/NP: <1%
D/F/W: 5.5%

Full grade history for CHEM 153A

What students say

dibs measures outcomes: grades, seats, how fast it fills. For what the class is actually like to sit in, BruinWalk has the reviews.

Workload, light. 3.4 of 5 for Ryan Lannan, where 5 is lightest. Read 15 days ago.

No assignment details are available in this review summary. Based on 246 reviews; source checked about 1 month ago. Missing details do not mean there are no papers or exams. Check the current syllabus.

CHEM 153A reviews for Ryan Lannan, one of 2 listed Reviews for all professors of CHEM 153A

Will it still be here

medium risk chance of closing before your enrollment pass.

Final enrollment per term from four years of grade data. Summer excluded: different population, different pass structure.

27722W
25122S
18122F
28123W
31823S
22223F
35024W
35024S
20424F
29825W
33525S
30025F

Peak 350 · most recent 25F at 300

Seats over time

Nothing read since 16 Oct, 7 hours ago. Over about 2 months before that, filled by 112.

7 times reopened

321 of 350 · 29 left in its discussions

18 Aug 18:4017 Sep 06:1616 Oct 17:53 · 7 hours ago

Checked 168 of the 597 hours with hourly history, 28%. No reading was recorded in 429 hours. dibs had no hourly record before 21 Sep, which is the other 819 of 1416 plotted.

A dot is a reading where something moved: the seat count, the status, or the waitlist. Flat between dots joins recorded counts; changes between reads may be missed. The line starts when dibs first saw this section rather than reaching back before it existed. The last one is the last time dibs read this section, moved or not, and that was 7 hours ago. It is where the line stops, not where the count is now.

Show the readings (92)

Recorded	Enrolled	Capacity	Status	Waitlist	Hours read
16 Oct 17:53	321	350	open	-	48 of 166
9 Oct 20:52	321	350	open	-	10 of 34
8 Oct 11:12	326	350	open	-	5 of 13
7 Oct 23:32	327	350	open	-	6 of 18
7 Oct 06:12	328	350	open	-	3 of 8
6 Oct 23:12	329	350	open	-	4 of 12
6 Oct 12:42	328	350	open	-	2 of 4
6 Oct 09:12	330	350	open	-	3 of 9
6 Oct 01:12	331	350	open	-	7 of 21
5 Oct 05:22	333	350	open	-	4 of 12
4 Oct 18:12	332	350	open	-	6 of 39
3 Oct 04:32	335	350	open	-	17 of 53
1 Oct 00:22	338	350	open	-	7 of 21
30 Sep 04:12	340	350	open	-	2 of 5
30 Sep 00:02	344	350	open	-	2 of 5
29 Sep 20:32	342	350	open	-	6 of 16
29 Sep 05:02	344	350	open	-	3 of 8
28 Sep 22:02	345	350	open	-	3 of 8
28 Sep 15:02	346	350	open	-	3 of 8
28 Sep 08:02	345	350	open	-	3 of 8
28 Sep 01:02	344	350	open	-	8 of 25
27 Sep 01:12	346	350	open	-	2 of 5
26 Sep 21:42	347	350	open	-	7 of 21
26 Sep 01:12	346	350	open	-	3 of 8
25 Sep 18:12	348	350	open	-	2 of 5
25 Sep 14:42	347	350	open	-	2 of 4
25 Sep 11:32	348	350	open	-	4 of 11
25 Sep 01:12	347	350	open	-	4 of 12
24 Sep 14:42	350	350	closed	-	4 of 11
24 Sep 04:12	349	350	open	-	2 of 6
23 Sep 23:42	350	350	closed	-	2 of 4
23 Sep 20:32	349	350	open	-	2 of 5
23 Sep 16:42	350	350	closed	-	5 of 14
23 Sep 03:52	349	350	open	-	2 of 4
23 Sep 00:22	350	350	closed	-	2 of 5
22 Sep 20:52	349	350	open	-	8 of 27, 3 no hourly record
21 Sep 18:32	350	350	closed	-	no hourly record
21 Sep 14:42	349	350	open	-	no hourly record
21 Sep 01:02	350	350	closed	-	no hourly record
20 Sep 21:42	349	350	open	-	no hourly record
20 Sep 19:22	350	350	closed	-	no hourly record
20 Sep 16:52	349	350	open	-	no hourly record
20 Sep 04:12	348	350	open	-	no hourly record
19 Sep 21:22	344	350	open	-	no hourly record
19 Sep 18:02	345	350	open	-	no hourly record
19 Sep 00:32	344	350	open	-	no hourly record
18 Sep 10:22	342	350	open	-	no hourly record
18 Sep 02:42	343	350	open	-	no hourly record
17 Sep 20:52	344	350	open	-	no hourly record
17 Sep 18:12	343	350	open	-	no hourly record
17 Sep 14:42	344	350	open	-	no hourly record
17 Sep 06:32	346	350	open	-	no hourly record
17 Sep 02:02	345	350	open	-	no hourly record
16 Sep 22:32	346	350	open	-	no hourly record
16 Sep 19:02	348	350	open	-	no hourly record
16 Sep 15:52	347	350	open	-	no hourly record
16 Sep 13:02	345	350	open	-	no hourly record
16 Sep 02:52	346	350	open	-	no hourly record
15 Sep 22:32	344	350	open	-	no hourly record
15 Sep 18:32	333	350	open	-	no hourly record
15 Sep 15:02	325	350	open	-	no hourly record
15 Sep 11:32	313	350	open	-	no hourly record
14 Sep 13:52	217	350	open	-	no hourly record
3 Sep 01:40	218	350	open	-	no hourly record
2 Sep 22:40	216	350	open	-	no hourly record
2 Sep 18:40	216	332	open	-	no hourly record
2 Sep 15:40	216	350	open	-	no hourly record
2 Sep 13:40	216	332	open	-	no hourly record
2 Sep 11:40	216	350	open	-	no hourly record
2 Sep 10:40	216	332	open	-	no hourly record
2 Sep 09:40	216	350	open	-	no hourly record
1 Sep 01:40	216	332	open	-	no hourly record
31 Aug 23:40	213	316	open	-	no hourly record
31 Aug 22:40	213	332	open	-	no hourly record
31 Aug 21:40	213	316	open	-	no hourly record
31 Aug 19:40	213	332	open	-	no hourly record
31 Aug 16:40	213	316	open	-	no hourly record
31 Aug 15:40	213	332	open	-	no hourly record
31 Aug 13:40	213	316	open	-	no hourly record
31 Aug 12:40	213	332	open	-	no hourly record
31 Aug 01:40	213	316	open	-	no hourly record
30 Aug 22:40	214	316	open	-	no hourly record
30 Aug 21:40	213	316	open	-	no hourly record
28 Aug 01:40	214	316	open	-	no hourly record
27 Aug 22:40	212	316	open	-	no hourly record
27 Aug 21:40	214	316	open	-	no hourly record
27 Aug 20:40	212	316	open	-	no hourly record
27 Aug 19:40	214	316	open	-	no hourly record
27 Aug 10:40	212	316	open	-	no hourly record
22 Aug 00:40	212	300	open	-	no hourly record
21 Aug 11:40	209	300	open	-	no hourly record
18 Aug 18:40	209	282	open	-	-

How readings and alerts work

Dated seat counts can be available even when hourly check history is missing. Gaps do not show whether seats changed between observations.

Seat counts show the last successful read, not live availability. Refreshes can be delayed by request limits or upstream interruptions. Watched sections receive priority, but an hourly update for every section is not guaranteed.

The registrar can change a seat count between our checks. Alerts depend on dibs detecting an opening and completing delivery; a quiet watch does not prove that no seat opened. Check the registrar before enrolling.

Class chat

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Seats, time, final and grades

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Before you can enroll

From the registrar Registrar note

Discussions

When it meets

Grades i An estimate based on historical registrar grades, not a student rating. Instructor estimates are pulled toward the course and department average in proportion to how little data there is, so a twelve-person seminar cannot top the list on noise. The sample size is printed beside it.

What students say

Will it still be here i The worse of two readings: how full this section is right now, and how quickly the course has historically filled. A tier rather than a percentage, because reserved seats make any number optimistic: an open seat may be held for a major or an intake you are not in.

Seats over time

Class chat

Grades

Will it still be here