Introduction

If you are preparing for the 10th class Chemistry board exam 2026, these most repeated questions from past papers (2018–2024) will help you achieve high marks.

These questions are collected from Lahore Board past papers and are considered very important for exam preparation. Many of these questions are repeated every year.

Basic Chemistry Concepts

State law of mass action (Repeated: 2018, 2019, 2021, 2022, 2024)
What are reversible reactions? (Repeated: 2018, 2020, 2023, 2024)
Define dynamic equilibrium (Repeated: 2019, 2020, 2023, 2024)
Types of chemical bonds (Repeated: 2019, 2021, 2022, 2023)
What is pH scale? (Repeated: 2018, 2021, 2023, 2024)

Organic Chemistry

Example of ester (Repeated: 2018, 2019, 2020, 2023, 2024)
Why are alkanes called paraffins? (Repeated: 2018, 2020, 2023, 2024)
Define structural formula (Repeated: 2019, 2021, 2022, 2023)
Where proteins are found (Repeated: 2019, 2020, 2022, 2021)

Environmental Chemistry

What is ozone depletion? (Repeated: 2019, 2020, 2023, 2024)
Uses of SO₃ (Repeated: 2018, 2021, 2023, 2024)
Temporary hardness of water (Repeated: 2019, 2021, 2023)
Solvay process ammonia recovery (Repeated: 2019, 2022, 2023)

Why These Questions Are Important?

These questions are frequently asked in board exams and have a high chance of appearing again in 2026. Preparing these questions will help you score better marks.

Final Tips for Students

Focus on repeated questions
Practice past papers
Revise important MCQs and short questions

Conclusion

These 10th class Chemistry most repeated questions are essential for students preparing for Lahore Board exams. Make sure to revise them multiple times before your exam.