ACS General Chemistry Exam 2026: Format, Time and National Norms
November 2, 2026 · Alex S. · reviewed by Hana N., Quality Reviewer · how we write
The full-year ACS General Chemistry exam has 70 multiple-choice questions in 110 minutes, or 112 minutes for the 2024 edition (GC24). ACS reports national norms instead of a pass mark.
The full-year ACS General Chemistry exam has 70 multiple-choice questions. Most editions allow 110 minutes, and the 2024 edition (GC24) allows 112. ACS does not set a pass mark. It reports national norms and sets no pass mark, so ask your instructor how the score counts.
Preparing for the ACS General Chemistry Exam? Take a free readiness test and see which topics to study first. Or see the ACS General Chemistry Exam study guide.
One subject, many exams
General chemistry comes in many ACS versions, so the first job is to find out which one you will sit. The current catalog lists these types:
| Type | Examples | Questions | Minutes |
|---|---|---|---|
| Full year | GC24, GC21, GC19 | 70 | 112 (GC24); 110 (earlier) |
| First term | GC25F, GC21F | 70 | 110 |
| Second term | GC22S, GC17S | 70 | 110 |
| Brief, full year | GC24B, GC18B | 50 | 55 |
| Brief, second term | GC24SB | 50 | 55 |
| Conceptual, full year | GC23C, GC16C | 60 | 110 |
| Conceptual, one term | GC23CF, GC23CS | 40 | 55 |
| Paired question, one term | GC17PQF, GC17PQS | 40 | 55 |
The catalog marks some older exams as inactive and lists two trial exams, GC27 and GC27S, with no question or time data yet.
How to read a norm sheet: the GC21 example
Because there is no cut score, the norm sheet is the main official yardstick. The GC21 sheet is based on the scores of 2,060 students from 17 institutions. Its summary statistics are:
- mean raw score: 37.8 out of 70;
- standard deviation: 12.7;
- median: 37;
- reliability (KR-21): 0.91.
The sheet then lists a percentile for every raw score. A few lines from it:
| Raw score (of 70) | Percentile on the GC21 sheet |
|---|---|
| 60 | 95 |
| 55 | 89 |
| 50 | 80 |
| 45 | 69 |
| 40 | 58 |
| 35 | 45 |
| 30 | 31 |
| 25 | 19 |
Five raw points can move you a long way: 40 sits at the 58th percentile and 45 at the 69th. Treat a percentile as a position in that group of students, not as a grade.
The 2024 exam has no norms yet
If your class uses GC24, there is no published norm sheet to compare with yet. The ACS page for GC24 says the test is not yet normed and asks instructors to contribute scores through score reporting. The national norms page lists general chemistry full-year forms only through 2021. Instructors who send scores get back the mean, standard deviation, median, reliability and standard error of measurement for their data. ACS also offers a norm reduction tool that lets an instructor remove items and see how the norms change.
Frequently asked questions
How many questions are on the ACS General Chemistry exam?
The full-year exam has 70 questions. Brief versions have 50, conceptual full-year versions have 60, and one-term conceptual and paired-question versions have 40.
How long is the ACS General Chemistry exam?
Full-year GC24 allows 112 minutes. Other active full-year, first-term and second-term editions allow 110 minutes. Brief versions allow 55.
What is a passing score on the ACS General Chemistry exam?
The ACS pages we checked list no passing score or cut score. ACS reports national norms, so ask your instructor how they count.
Is the ACS General Chemistry exam the same length as the organic exam?
Both full-year exams have 70 questions. General Chemistry allows 110 minutes (112 for GC24) and Organic allows 110. Each exam has its own norm sheet.
Official sources
- ACS Exams Institute: exams catalog (questions and time limits)
- ACS Exams Institute: 2024 General Chemistry Exam, Full Year (GC24)
- ACS Exams Institute: GC21 norm sheet (PDF)
- ACS Exams Institute: national norms
- ACS Exams Institute: score reporting
Checked against the sources above on November 2, 2026. Exam bodies change fees and rules: confirm on the official page before you register.