Join WhatsApp ChannelDaily MCQs & Exam Updates

Chemistry MCQs

74 Questions Subject Test
Subject Preparation Guide

Prepare Chemistry with confidence

Practice the essential concepts of matter, atomic structure, chemical reactions, bonding and everyday applications of chemistry.

Atomic StructureChemical BondingReactionsOrganic Chemistry
Helpful for board examinations, entry tests and science-based competitive papers.
Chemistry preparation illustration
Subject Test

Test your Chemistry preparation

Questions are tracked as practiced when you open Show Answer & Explanation. Tracking stays only in this browser tab and no subject-test result is saved.

Practiced MCQs
0 / 74
Use the MCQs you already prepared, or launch a random test from the full subject bank.
No login required Result is not saved Choose your own MCQ count & timer
Choose your test mode
Choose any number up to 74 available MCQs.
Enter 0 for no timer, or choose 1–300 minutes.
Tip: prepare some MCQs first, then start a quick self-check from My Practiced MCQs to test exactly what you studied.
Filter: All Exams css pms fpsc ppsc nts | All Easy Medium Hard
61
Medium css fpsc ppsc Uploaded: 14 Jul 2026

Which chemical process is used to extract metals from their ores using carbon or electrolysis?

  • A Reduction
  • B Oxidation
  • C Neutralisation
  • D Chromatography
Permalink
Correct Answer: Option A — Reduction
Explanation: Reduction is used to extract metals from their ores by removing oxygen using a reducing agent like carbon or by electrolysis for more reactive metals like aluminium.
Submitted by: PaperMCQs
62
Medium fpsc ppsc nts Uploaded: 05 Aug 2026

What gas is produced when calcium carbonate is heated strongly in thermal decomposition?

  • A Oxygen
  • B Sulfur dioxide
  • C Carbon dioxide
  • D Carbon monoxide
Permalink
Correct Answer: Option C — Carbon dioxide
Explanation: Heating calcium carbonate strongly causes thermal decomposition producing calcium oxide quicklime and carbon dioxide gas a reaction widely used in cement production and lime kilns.
Submitted by: PaperMCQs
63
Medium css fpsc ppsc Uploaded: 14 Jul 2026

What is the role of a catalyst in a chemical reaction?

  • A Increases activation energy
  • B Is consumed by the reaction
  • C Changes the products formed
  • D Increases reaction rate without being consumed
Permalink
Correct Answer: Option D — Increases reaction rate without being consumed
Explanation: A catalyst increases the rate of a chemical reaction by providing an alternative reaction pathway with lower activation energy and is not consumed or permanently changed during the process.
Submitted by: PaperMCQs
64
Medium fpsc ppsc nts Uploaded: 14 Jul 2026

Which type of chemical reaction involves a substance combining with oxygen to release energy?

  • A Reduction
  • B Oxidation
  • C Neutralisation
  • D Decomposition
Permalink
Correct Answer: Option B — Oxidation
Explanation: Oxidation involves the combination of a substance with oxygen releasing energy often as heat and light as seen in combustion reactions such as burning wood or fuels.
Submitted by: PaperMCQs
65
Medium fpsc ppsc nts Uploaded: 14 Jul 2026

Which type of hydrocarbon contains at least one carbon to carbon double bond?

  • A Alkane
  • B Alkyne
  • C Alkene
  • D Arene
Permalink
Correct Answer: Option C — Alkene
Explanation: Alkenes are unsaturated hydrocarbons containing at least one carbon to carbon double bond making them more reactive than alkanes and important in polymer production.
Submitted by: PaperMCQs
66
Medium ppsc Uploaded: 06 Aug 2026

Which element is essential for photosynthesis and found in chlorophyll?

  • A Iron
  • B Magnesium
  • C Zinc
  • D Calcium
Permalink
Correct Answer: Option B — Magnesium
Explanation: Magnesium is a central component of the chlorophyll molecule, which plants use to capture light energy during photosynthesis. Without adequate magnesium, plants cannot efficiently convert sunlight into chemical energy.
Submitted by: PaperMCQs
67
Medium css fpsc ppsc Uploaded: 14 Jul 2026

Which type of formula shows all the bonds between atoms in a molecule?

  • A Empirical formula
  • B Structural formula
  • C Molecular formula
  • D Ionic formula
Permalink
Correct Answer: Option B — Structural formula
Explanation: A structural formula shows all the atoms in a molecule and the bonds between them either as a displayed formula showing each bond or as a condensed structural formula.
Submitted by: PaperMCQs
68
Medium css fpsc ppsc Uploaded: 05 Aug 2026

Which type of organic reaction adds atoms across a carbon to carbon double bond in alkenes?

  • A Substitution
  • B Addition
  • C Elimination
  • D Hydrolysis
Permalink
Correct Answer: Option B — Addition
Explanation: Addition reactions are characteristic of alkenes where atoms or groups add across the carbon-carbon double bond breaking it and forming two new single bonds with the carbon atoms.
Submitted by: PaperMCQs
69
Medium fpsc ppsc nts Uploaded: 14 Jul 2026

What is the chemical formula for sulfur dioxide a gas that causes acid rain?

  • A SO3
  • B S2O
  • C SO
  • D SO2
Permalink
Correct Answer: Option D — SO2
Explanation: Sulfur dioxide SO2 is produced by burning fossil fuels containing sulfur and when it reacts with atmospheric moisture it forms sulfurous and sulfuric acid contributing to acid rain.
Submitted by: PaperMCQs
70
Medium fpsc ppsc nts Uploaded: 14 Jul 2026

What is the chemical formula for glucose, the primary energy source for cells?

  • A C6H10O5
  • B C12H22O11
  • C C6H12O6
  • D C6H6O6
Permalink
Correct Answer: Option C — C6H12O6
Explanation: Glucose has the chemical formula C6H12O6 and is a monosaccharide sugar that serves as the primary energy source for cellular respiration in living organisms.
Submitted by: PaperMCQs
71
Medium css fpsc ppsc Uploaded: 14 Jul 2026

What does Avogadro's number represent?

  • A Number of atoms in 1 gram of hydrogen
  • B Number of particles in one mole of a substance
  • C Number of molecules in 1 litre of gas
  • D Number of protons in a nucleus
Permalink
Correct Answer: Option B — Number of particles in one mole of a substance
Explanation: Avogadro's number is approximately 6.022 x 10 to the power 23 and represents the number of atoms molecules or ions contained in one mole of any substance.
Submitted by: PaperMCQs
72
Medium css fpsc ppsc Uploaded: 05 Aug 2026

Which process hardens rubber by adding sulfur making it stronger and more elastic?

  • A Vulcanisation
  • B Saponification
  • C Hydrogenation
  • D Polymerisation
Permalink
Correct Answer: Option A — Vulcanisation
Explanation: Vulcanisation is the process of treating rubber with sulfur at high temperature creating cross-links between polymer chains making the rubber harder more durable and resistant to temperature changes.
Submitted by: PaperMCQs
73
Medium css fpsc ppsc Uploaded: 14 Jul 2026

What is formed when an alcohol reacts with a carboxylic acid?

  • A Ester and water
  • B Salt and water
  • C Soap
  • D Alkene and water
Permalink
Correct Answer: Option A — Ester and water
Explanation: When an alcohol reacts with a carboxylic acid an esterification reaction occurs producing an ester and water and this reaction requires an acid catalyst such as concentrated sulfuric acid.
Submitted by: PaperMCQs
74
Medium ppsc Uploaded: 07 Aug 2026

What is the density of pure water at 4°C?

  • A 2.0 g/cm3
  • B 0.5 g/cm3
  • C 1.0 g/cm3
  • D 1.5 g/cm3
Permalink
Correct Answer: Option C — 1.0 g/cm3
Explanation: Pure water reaches its maximum density of 1.0 g/cm3 at 4°C, which is used as the reference standard for specific gravity measurements. This unique property causes ice to float since it is less dense than liquid water.
Submitted by: PaperMCQs
All Subjects
Biology 210 Chemistry 235 Computer Science 477 Current Affairs 1,079
1–4 of 11Auto-changing every 5s
Academic Subjects
Physics9th Class 248
View All Academic Classes
Mock Tests
Quick Test (20 Q) Full Mock Test
Practiced MCQs0 / 74