Skip to content

Sign in Sign up free

JEE Main Mole Concept and Stoichiometry questions with solutions

Mole, molar mass, empirical formulae, limiting reagent, concentration terms, gas laws and stoichiometric calculations. 12 questions from our 2016–2025 JEE Main pattern papers, from the Class 11 Chemistry syllabus. Each has the answer and a full solution.

Also practise: Mole Concept and Stoichiometry for JEE Advanced · Mole Concept and Stoichiometry for NDA

JEE Main 2025

A 1.84 g mixture of CaCO3 and MgCO3 (molar masses 100 and 84 g mol^-1) on strong heating liberates 0.448 L of CO2 measured at STP (22.4 L mol^-1).…JEE Main 2025 · medium
0 mL of a commercial H2O2 sample is diluted to 100 mL. 10 mL of the diluted solution exactly decolourises 20 mL of 0.1 M acidified KMnO4. The…JEE Main 2025 · medium

JEE Main 2024

A 5.00 g mixture of NaHCO3 and Na2CO3 loses 0.93 g on strong heating to constant mass. The volume of 1.00 M HCl needed to react completely (to CO2)…JEE Main 2024 · medium

JEE Main 2023

A 2.00 g mixture of CaCO3 and MgCO3 is strongly heated until both decompose completely to oxides, releasing 0.947 g of CO2. Taking molar masses…JEE Main 2023 · medium

JEE Main 2022

JEE Main 2021

A 9.2 g mixture of CaCO3 and MgCO3 is strongly heated until only the oxides remain; the residue weighs 4.8 g. The mass percentage of CaCO3 in the…JEE Main 2021 · medium

JEE Main 2020

A 10.0 g mixture of CaCO3 and MgCO3 is heated strongly until no more gas is evolved and the solid residue (CaO+MgO) weighs 5.27 g. Taking molar…JEE Main 2020 · medium

JEE Main 2019

A 1.330 g mixture of NaCl and KCl is dissolved in water and treated with excess AgNO3, giving 2.870 g of AgCl. (Na = 23, K = 39, Cl = 35.5, Ag =…JEE Main 2019 · easy

JEE Main 2018

A 2.000 g mixture of CaCO3 and MgCO3 is strongly heated until only the oxides remain; the residue weighs 1.036 g. Taking molar masses CaCO3=100…JEE Main 2018 · medium

JEE Main 2017

A 5.00 g sample containing only NaHCO3 and Na2CO3 loses 0.62 g on strong heating (the carbonate is stable). The unheated 5.00 g sample is dissolved…JEE Main 2017 · medium

JEE Main 2016

32 g of crystalline sodium carbonate, Na2CO3· xH2O, needs 40.0 mL of 0.500 M HCl for complete neutralisation to CO2. Taking Na=23, C=12, O=16, H=1…JEE Main 2016 · easy

Other Chemistry topics

Alcohols, Phenols, Ethers and Haloalkanes 16 Atomic Structure 12 Biomolecules and Polymers 14 Carbonyl Compounds, Carboxylic Acids and Amines 25 Chemical Bonding and Molecular Structure 14 Chemical Equilibrium 10 Chemical Kinetics 13 Chemical Thermodynamics 16 Coordination Compounds 18 Electrochemistry 18 General Organic Chemistry and Isomerism 13 Hydrocarbons 16 Ionic Equilibrium 11 Periodic Properties 9 Qualitative and Practical Chemistry 8 Redox Reactions and Titrations 9 Solutions, Solid State and Surface Chemistry 19 d- and f-Block Elements and Metallurgy 14 s-Block, p-Block Elements and Hydrogen 23