Clinical Chemistry Practice Questions (ASCP MLS and MLT)
20–25% of the MLT exam · 17–22% of the MLS exam, in ASCP’s content guidelines
100 questions across all seven content areas in 2 hours 30 minutes, with a score for Chemistry so you know where you stand.
Free Chemistry drillWhich ion-selective electrode uses a valinomycin membrane?
Chemistry on the ASCP exams
Chemistry is 20–25% of the MLT exam, the largest share with hematology, and 17–22% of the MLS exam. Questions combine test principles, specimen handling, interfering substances, calculations and the disease states each result points to.
- Share of the exam
- MLT 20–25% (22 of 100 on our MLT mock) · MLS 17–22% (20 of 100 on our MLS mock)
- Our drill
- 10 questions from 80 chemistry questions, untimed, an explanation after every answer; one free attempt, unlimited with a pass
What Chemistry questions test
- Carbohydrates and lipids: glucose methods, diabetes criteria, A1c, lipoproteins and the Friedewald LDL calculation
- Heme derivatives and enzymes: bilirubin fractions and jaundice patterns, liver, cardiac and pancreatic enzymes, isoenzymes and kinetics
- Proteins and nitrogen compounds: electrophoresis patterns, albumin and total protein methods, BUN, creatinine and clearance, uric acid, ammonia, cardiac and tumor markers
- Acid-base and electrolytes: blood gas interpretation, the anion and osmolal gaps, calcium, magnesium, iron studies and transferrin saturation
- Endocrinology, vitamins, TDM and toxicology: thyroid and adrenal patterns, immunoassay interferences, peak and trough timing, specimen types and confirmation testing
Sit the full exam under the real clock
100 questions across all seven content areas in 2 hours 30 minutes, with a score for Chemistry so you know where you stand.
Free Chemistry drillHow to study it
- Learn blood gases with one routine: pH first, then the primary cause, then compensation.
- Memorize ASCP’s chemistry reference ranges and the calculations it lists; they are not given on the exam.
- For each analyte, know the specimen rule that ruins it: hemolysis, light, glycolysis or the wrong tube.
Common questions
How much chemistry is on the ASCP MLT exam?
Chemistry is 20–25% of the MLT exam and 17–22% of the MLS exam. Our MLT mock has 22 chemistry questions and our MLS mock 20.
Which chemistry calculations should I know?
ASCP lists % transferrin saturation, UIBC and TIBC, indirect bilirubin, LDL by Friedewald and non-HDL cholesterol, the A/G ratio, timed urine and creatinine clearance calculations and Beer’s law. The calculations drill practices them.
100 questions across all seven content areas in 2 hours 30 minutes, with a score for Chemistry so you know where you stand.
Free Chemistry drillThe other content areas
Sources
- ASCP BOC: MLT and MLS Examination Content Guidelines (revised June 9, 2026)
- ASCP BOC: About the Examination (format, CAT, scoring, field test questions, calculator)
- ASCP BOC: Medical Laboratory Technician, MLT(ASCP): eligibility routes and $235 fee
- ASCP BOC: Medical Laboratory Scientist, MLS(ASCP): eligibility routes and $260 fee
- ASCP BOC: Examination Results
- ASCP BOC: After the Examination (re-applying, five attempts per route, 30-day wait)
- ASCP BOC: Schedule or Reschedule Your Examination (Pearson testing centers)
- ASCP BOC: MLS and MLT Credential Maintenance Program requirements (36 points, three years)
Original practice questions for exam preparation, written to the ASCP BOC MLT and MLS Examination Content Guidelines (revised June 9, 2026), not ASCP exam questions. Independent practice, not affiliated with or endorsed by the American Society for Clinical Pathology (ASCP), the ASCP Board of Certification or Pearson VUE.