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JEE-MAIN SERIES
Chemistry

Molecular Empirical Formula

6 previous year questions.

Volume: 6 Ques
Yield: Medium

High-Yield Trend

5
2026
1
2025

Chapter Questions
6 MCQs

01
PYQ 2025
medium
chemistry ID: jee-main
On complete combustion 1.0 g of an organic compound (X) gave 1.46 g of CO₂ and 0.567 g of H₂O. The empirical formula mass of compound (X) is:
(Given molar mass in g mol : C: 12, H: 1, O: 16)
1
30
2
45
3
60
4
15
02
PYQ 2026
medium
chemistry ID: jee-main
Which of the following contain the same number of atoms? (Given : Molar mass in g mol of H, He, O and S are and respectively)}
  • [A.] of gas
  • [B.] of gas
  • [C.] of at STP
  • [D.] of He at STP
  • [E.] of gas
Choose the correct answer from the options given below:
1
A and B only
2
B and C only
3
C and D only
4
A, C and E only
03
PYQ 2026
medium
chemistry ID: jee-main
What volume of hydrogen gas at STP would be liberated by action of 50 mL of of 50% purity (density ) on 20 g of zinc?
Given : Molar mass of H, O, S, Zn are 1, 16, 32, 65 respectively.
1
5.824 L
2
7.428 L
3
6.892 L
4
8.375 L
04
PYQ 2026
medium
chemistry ID: jee-main
36 g of A reacts with 54 g of B to form AB , if the molar mass of A and B is respectively 60 and 80, then choose the correct option from the following.
1
Limiting Reagent is A
2
90 g of AB formed
3
Limiting Reagent is B
4
50 g of AB formed
05
PYQ 2026
medium
chemistry ID: jee-main
Consider the following data: Find the lattice energy of NaCl(s).
1
-786 kJ mole
2
-628 kJ mol
3
-428 kJ mole
4
-393 kJ mole
06
PYQ 2026
medium
chemistry ID: jee-main
Consider the statements below: Statement I: BCl is covalent in nature. Statement II: BCl undergoes hydrolysis to form [B(OH) ] and BH . In the light of the above statements, choose the correct option.
1
Statement I and Statement II both are correct
2
Statement I and Statement II both are incorrect
3
Statement I correct, Statement II incorrect
4
Statement I incorrect, Statement II correct

About Molecular Empirical Formula - JEE-MAIN

Molecular Empirical Formula is a vital chapter for JEE-MAIN aspirants. Mastering the concepts covered in this chapter is essential for securing a top rank.

By rigorously practicing the previous year questions associated with this chapter, you can identify high-yield topics, understand the examiner's perspective, and boost your confidence during the actual exam.

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Analyzing PYQs for this specific chapter reveals the most frequently tested concepts and the typical complexity of questions, allowing you to tailor your study plan efficiently.

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