MDCAT Chemistry — Gases
Gases is a core Chemistry topic in the PMDC MDCAT syllabus, covering 9 subtopics. Below are the subtopics to revise, how often the topic appears in past papers, and real past-paper MCQs to try.
Subtopics (9)
- Absolute Zero
- Boyle's Law
- Ideal Gas Constant (R)
- Ideal Gas Equation
- Kinetic Molecular Theory
- Plasma State of Matter
- Real and Ideal Gases
- Standard Temperature and Pressure
- States of Matter
How Gases is tested
Across the 16 MDCAT past papers on ParhaiKrlo, Gases accounts for 38 questions. It appears in 14 of them, about 2.7 questions a paper. The heaviest was MDCAT 2022, with 4 questions, and the most recent is MDCAT 2025, with 3.
| Paper | Questions |
|---|---|
| MDCAT 2025 | 3 |
| MDCAT 2024 | 3 |
| MDCAT 2023 | 2 |
| MDCAT 2022 | 4 |
| MDCAT 2019 | 1 |
| MDCAT 2018 | 4 |
| MDCAT 2017 | 2 |
| MDCAT 2016 | 3 |
| MDCAT 2015 | 3 |
| MDCAT 2014 | 2 |
| MDCAT 2013 | 1 |
| MDCAT 2010 | 4 |
| MDCAT 2009 | 3 |
| MDCAT 2008 | 3 |
Gases MCQs from the MDCAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · MDCAT 2025 · Gases
Value of R (gas constant) in J mol⁻¹ K⁻¹ is
- A.8.314
- B.62.4
- C.0.821
- D.62400
Show answer
Answer: A. 8.314 — The gas constant R = 8.314 J mol⁻¹ K⁻¹.
- Q2 · MDCAT 2024 · Gases
Intermolecular forces between molecules of ideal gas are
- A.Strong
- B.Moderate
- C.Weak
- D.Absent
Show answer
Answer: D. Absent — Ideal gas theory assumes intermolecular forces between gas molecules are essentially absent.
- Q3 · MDCAT 2023 · Gases
Which one of the following gases has the lowest density under room conditions?
- A.Neon
- B.Nitrogen
- C.Oxygen
- D.Fluorine
Show answer
Answer: A. Neon — Neon has the lowest density among these gases under room conditions, since it has the smallest molar mass.