Chemistry Class 9 Chapter 8: Energetics

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• Class 9
• Chemistry
• Chapter 8
• FBISE SSC-I

Chapter summary

Chapter 8 of Chemistry for Class 9 is called "Energetics". It covers 10 learning outcomes of the Federal Board syllabus. You will learn to: explain the idea of a chemical system and its connection; differentiate between exothermic and endothermic reactions on any three points and give one example of each. Parhayi.com has 463 MCQs, 109 short questions and 20 long questions for this chapter.

Topics in this chapter

• Explain the idea of a chemical system and its connection…
• Differentiate between exothermic and endothermic reactions on any three points and give one example of each
• State that thermal energy is called enthalpy change and…
• Define activation energy as the minimum energy that…
• Explain that activation energy depends on reaction…
• Draw, label and interpret reaction pathway diagram for…
• Recognize that bond breaking is endothermic and bond…
• Explain that enthalpy change is sum of energies absorbed…
• Calculate enthalpy change of a reaction given bond energy…
• Explain how respiration (aerobic and anaerobic), an…

Sample questions

Try these questions from the chapter. The answers are for Premium students.

1. Define the terms 'system' and 'surroundings'. When limestone reacts with dilute hydrochloric acid in a test tube, what is the system and what are the surroundings? (3 marks)
2. What is the relation between activation energy and rate of reaction? Explain with an example. (3 marks)
3. Calculate the enthalpy: H₂(g) + I₂(g) → 2HI(g), ΔH° = ? Bond energies: H–H = 436 kJ/mol, I–I = 151 kJ/mol, H–I = 299 kJ/mol (3 marks)

What Premium gives you in this chapter

• 463 MCQs with answers and explanations
• 109 short questions with full answers
• 20 long questions with answers
• 13 Learn cards
• 29 Activities and games
• chapter tests that show your weak topics

Chemistry is the study of matter and how it changes. Learn the definitions first, then practise equations, balancing and numericals until they feel easy.