Atoms and Molecules

12 solved questions from Class 9 Science, each with the full working. Tap any question to see the step-by-step solution.

• 1 What is the fundamental scientific concept introduced in the chapter 'Atoms and Molecules'? medium MCQ Key Concept & Definition
• 2 Which of the following is an important application or observation related to 'Atoms and Molecules'? easy MCQ Practical Application
• 3 What primary question does the chapter 'Atoms and Molecules' aim to answer? medium MCQ Core Scientific Inquiry
• 4 Why is the study of 'Atoms and Molecules' essential for students in class-9? hard MCQ Importance & Significance
• 5 Which key practice is recommended while studying topics in 'Atoms and Molecules'? medium MCQ Scientific Method
• 6 What is the primary topic or theoretical principle explored in 'Atoms and Molecules' (Class 9 SCIENCE)? medium MCQ Chapter Core Principle
• 7 Which key mechanism or analytical rule is highlighted in 'Atoms and Molecules'? medium MCQ Key Analytical Mechanism
• 8 An atom has mass number 12 and atomic number 6. How many protons does it have? easy MCQ 1 mark Atomic number and protons
• 9 According to Avogadro's hypothesis, how many liters of a gas will occupy 3 moles at standard temperature and pressure (STP)? medium 2 marks Avogadro's hypothesis
• 10 Write the empirical formula of a compound that contains 60 % carbon and 40 % hydrogen by mass. medium 2 marks Empirical formula calculation
• 11 Balance the chemical equation: C2H5OH + O2 -> CO2 + H2O. Use the balanced equation to show conservation of atoms. hard 4 marks Balancing chemical equations
• 12 How many atoms are present in 2 moles of sodium atoms? medium 2 marks Atom count from moles