Chemistry Class 9 Chapter 3: Atomic Structure

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• Class 9
• Chemistry
• Chapter 3
• FBISE SSC-I

Chapter summary

Chapter 3 of Chemistry for Class 9 is called "Atomic Structure". It covers 20 learning outcomes of the Federal Board syllabus. You will learn to: explain the structure of the atom as a central nucleus; state that, orbits (shells) are energy levels of. Parhayi.com has 441 MCQs, 111 short questions and 20 long questions for this chapter.

Topics in this chapter

• Explain the structure of the atom as a central nucleus…
• State that, orbits (shells) are energy levels of…
• Explain that a nucleus is made up of protons and neutrons…
• State the relative charge and relative masses of a…
• Interpret the relationship between a subatomic particle…
• Illustrate the path that positively and negatively…
• Define proton number/atomic number as the number of…
• Explain that the proton number is unique to each element…
• State that radioactivity can change the proton number and…
• Define nucleon number/atomic mass as sum of number of…
• Define isotopes as different atoms of the same element…
• State that isotopes can affect molecular mass but not…
• Determine the number of protons and neutrons of different…
• Define relative atomic mass as the average mass of…
• State that isotopes can exhibit radioactivity
• Discuss the importance of isotopes using carbon dating…
• Describe the formation of positive (cation) and negative…
• Interpret and use the symbols for atoms and ions
• Calculate relative atomic mass of an element from…
• Calculate relative atomic mass of an element from…

Sample questions

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

1. Draw Bohr's model for the following atoms indicating the location of electrons, protons and neutrons: (a) Carbon (C) (b) Magnesium (Mg) (3 marks)
2. Isotopes of an element have the same chemical properties but can have different physical properties. Explain, using heavy water as an example. (3 marks)
3. Calculate the relative molecular masses of H³⁵Cl and H³⁷Cl (H = 1). (3 marks)

What Premium gives you in this chapter

• 441 MCQs with answers and explanations
• 111 short questions with full answers
• 20 long questions with answers
• 13 Learn cards
• 40 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.