Texas Chemistry CBE Exam Format — 50 Questions, 3 Hours, and What the Official Guide Says

The Texas Chemistry Credit by Examination is not a mystery exam. UT High School publishes a free study guide for each semester, and those guides state the shape of the paper outright: fifty multiple-choice questions, three hours, two points per question, one hundred points. No essays. A calculator is not merely allowed — it is required.

What the guides do not publish is how many questions come from each topic. That silence is itself worth understanding, and it changes how you should prepare.

The shape of the paper

Three hours for fifty questions is three and a half minutes per question. That is generous arithmetic and unforgiving concentration. The exam does not run out of time on most students; it runs out of attention.

Chemistry A — the four topics

The study guide isolates four topics and gives study tips and sample questions for each:

• Topic 1 — Scientific Methods and Chemical Safety. Lab safety, the scientific method, observation versus inference, accuracy versus precision, significant figures.
• Topic 2 — Science and Society. The one most students never revise. How chemistry meets public policy, ethics, and everyday life.
• Topic 3 — The Periodic Table and Trends. Arrangement, groups and periods, atomic radius, ionisation energy, electronegativity.
• Topic 4 — Atoms, Atomic Theory and Compounds. Atomic structure, isotopes, electron configuration, nomenclature, bonding and compound formation.

Notice what is not a headline topic: stoichiometry. It belongs to Semester B.

Chemistry B — the six topics

• Topic 1 — Matter in Chemical Substances
• Topic 2 — Matter in Chemical Reactions
• Topic 3 — Gas Behavior
• Topic 4 — Solutions
• Topic 5 — Energy in Reactions
• Topic 6 — Nuclear Chemistry

A small honesty note, because we would rather you hear it from us than be confused on the day: the Chemistry B guide’s own introduction announces “7 key topics” and then lists six. Its body carries study tips for Topics 1 through 6 and no seventh. We are reporting the six the document actually covers.

What the guide does not tell you

It does not publish a per-topic question count. An older edition of the Chemistry guide, dated December 2013, did — it broke Semester A into five parts with an exact number of questions each. The current guides, dated September 2024, dropped that breakdown.

If you find a blog or a forum post quoting “15 questions on scientific methods, 10 on the periodic table,” it is quoting a study guide that is more than a decade old and no longer describes this exam. Treat any per-topic count you read online, including one you may have read here before today, as unsupported by the current source.

What follows from that is simple. You cannot weight your revision to a blueprint that is no longer published. Prepare across all topics of the semester, and let the sample questions in the official guide calibrate depth rather than proportion.

Bring a calculator. Do not memorise the periodic table.

• A #2 pencil; the answer sheet is computer-graded and given to you.
• A scientific or graphing calculator is required — not optional. Arriving without one is a self-inflicted wound.
• A periodic table and a formula sheet are provided with the exam.

Both reference sheets are printed inside the study guide, which means you can practise with the exact materials that will be on the desk. Speed of lookup is a skill worth drilling. Memorising a constant that will be handed to you is not.

The passing score depends on why you are taking it

Texas runs two routes through Credit by Examination, and they do not share a passing score. The study guides themselves do not state one — it comes from the administering institution’s policy.

• Examination for Acceleration — 80%. No prior instruction in the course; you are skipping it. Texas Education Code §28.023.
• Credit by Examination with prior instruction — 70%. You took the course and are recovering the credit. 19 TAC §74.24.

On a hundred-point paper, that is the difference between missing ten questions and missing fifteen. Settle which route you are on before you set a target score. The guides are titled “CBE CR/A” precisely because one document serves both.

Which TEKS?

High-school Chemistry is defined by 19 TAC §112.43, adopted by the State Board of Education in November 2020 and implemented in 2023–24. Older material — including the 2013 study guide — cites the former section, §112.35. If a resource still points you there, check its date before you trust anything else in it.

How to prepare

• Cover every topic of your semester. With no published weighting, a gap is a real risk rather than an acceptable trade.
• Practise with the provided periodic table and formula sheet from day one.
• Do not skip Science and Society. It is a listed topic of Chemistry A and the one almost nobody revises.
• Sit the whole thing under a clock at least once. Fifty questions across three hours is an attention test disguised as a chemistry test.

Texas CBE™ Chemistry practice

Our Chemistry practice covers both semesters with a written explanation on every question, and timed mock exams that run at the real fifty-question, three-hour pace. Questions are independently authored and TEKS-driven; we do not reproduce UTHS sample questions. Free sample questions are available without an account.

Not affiliated with UT High School, the University of Texas at Austin, Texas Tech University K-12, the Texas Education Agency, or any school district. Texas CBE™ is an independent, TEKS-aligned practice resource. Exam structure, policies and passing standards are set by the administering institution and change over time — this article reflects the study guides dated September 2024. Always confirm against the current official study guide before you rely on it.