U.S. National Chemistry Olympiad.

An introduction

The only three-part chemistry paper on this shelf.

The USNCO is unusual in this library because of its lab component. Most olympiads end at the written paper. USNCO's National exam includes Part III — a real, ninety-minute, supplied-equipment wet lab — that no amount of textbook study can replace. A student preparing for the National exam needs lab time as well as theory time, which makes USNCO advancement strongly dependent on school chemistry-lab access.

The pathway begins with a Local Exam in early spring — a 60-question MCQ in 110 minutes, administered by ACS local sections (for 2026, the local testing window runs late February into mid-March). Top scorers are invited to the National Exam in April, which runs the three parts across a single day. The top twenty students attend the two-week Study Camp at the University of Maryland, College Park, in late May into June; four are selected for the International Chemistry Olympiad in July. Confirm this year's exact dates against the official ACS page below.

Parts at a glance

Same content, three forms.

Part	Format	What it tests
Local Exam	60 MC · 110 min	Breadth across general chemistry.
National Part I	60 MC · 90 min	Same MCQ form, harder questions, tighter pace.
National Part II	8 long problems · 105 min	Show all working. Multi-step derivations.
National Part III	2 lab tasks · 90 min	Real wet lab; supplied equipment; safety rules enforced.

A note on access

Why our HTML coverage is partial.

The five ACS HTML pages we'd most like to capture (eligibility, registration pathway, award tiers, study-camp invitation logic, calendar) are behind the Incapsula JS-challenge. Our published reader-facing playbook is structured to work from the 12 verified PDFs and to flag the five gated surfaces as “promote-only-after-real-content-HTML-capture”.