cbse class 9 science chapter 4 case study questions

Class 9 Science Case Study Questions Chapter 4 Structure of Atom

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Case study Questions on Class 9 Science Chapter 4  are very important to solve for your exam. Class 9 Science Chapter 4 Class 9 Science Case Study Questions have been prepared for the latest exam pattern. You can check your knowledge by solving  case study-based questions for Class 9 Science  Chapter 4 Structure of Atom

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In CBSE Class 9 Science Paper, Students will have to answer some questions based on Assertion and Reason. There will be a few questions based on case studies and passage-based as well. In that, a paragraph will be given, and then the MCQ questions based on it will be asked.

Structure of Atom Case Study Questions With Answers

Here, we have provided case-based/passage-based questions for Class 9 Science  Chapter 4 Structure of Atom

Case Study/Passage-Based Questions

Case Study 1: The maximum number of electrons that are permitted to be assigned to an energy shell of an atom is called the electron capacity of that shell. The distribution of electrons in different orbits or shells is governed by a scheme known as the Bohr-Bury scheme. According to this scheme : (i) The maximum number of electrons that can be present in any shell is given by the formula 2n2 where n is the number of energy levels. (ii) The maximum number of electrons that can be accommodated in the outermost shell is 8. Electrons are filled in the shells in a stepwise manner in increasing the order of energy of the energy shell.

What is the maximum electron capacity of the N shell? (a) 24 (b) 8 (c) 18 (d) 32

Answer: (d) 32

Identify the element with the configuration K-2, L-8, M-3. (a) Aluminium (b) Magnesium (c) Sodium (d) Beryllium

Answer: (a) Aluminium

Which of the following configuration represent sodium? (a) 2, 8, 4 (b) 2, 8, 5 (c) 2, 3 (d) 2, 8, 1

Answer: (d) 2, 8, 1

Case Study/Passage Based Questions

The given diagrams show the atomic structures of elements X and Y.

Element X and Y could be _ and _ respectively. (a) Be and B (b) C and O (c) F and N (d) C and N

Answer: (d) C and N

Valency of elements X and Y are respectively, (a) 4 and 3 (b) 2 and 5 (c) 1 and 4 (d) 3 and 4

Answer: (a) 4 and 3

Elements X and Y are (a) isotopes (b) isoelectronic (c) isobars (d) isomers.

Answer: (c) isobars

Case Study 2: The mass of an atom is due to the masses of protons and neutrons in the nucleus. The relative masses of protons and neutrons are almost equal to one. Therefore, the atomic mass of an element should be nearly a whole number. But in many cases the atomic masses are fractional. The main reason for these fractional atomic masses is that these elements occur in nature as a mixture of several isotopes. The atomic mass of an element is the average of the atomic masses of these isotopes in the ratio of their proportion of occurrence.

Chlorine occurs in nature in the form of two isotopes with atomic masses 35 u and 37 u in the ratio of 3 : 1 respectively. The atomic mass of chlorine is (a) 35.5 u (b) 34.5 u (c) 35 u (d) 36 u

Answer: (a) 35.5 u

An element occurs in two isotopic forms with atomic masses 10 and 11. What is the percentage abundance of two isotopes in the sample having an atomic mass of 10.80? (a) 20, 80 (b) 50, 50 (c) 25, 70 (d) 60, 40

Answer: (a) 20, 80

The fractional atomic masses of elements are due to the existence of (a) isotopes having different masses (b) diagonal relationship (c) equal number of electrons and protons (d) none of these.

Answer: (a) isotopes having different masses

Case Study 3: The structure of an atom consists of subatomic particles, mainly protons, neutrons, and electrons. Protons and neutrons are located in the nucleus, which is the central region of an atom. Protons carry a positive charge, while neutrons are electrically neutral. Electrons, on the other hand, are negatively charged particles that orbit around the nucleus in energy levels or shells. The number of protons in an atom determines its atomic number, which is unique to each element. The mass number of an atom is the sum of its protons and neutrons. The atomic mass of an element is the weighted average mass of all its naturally occurring isotopes. Isotopes are atoms of the same element that have different numbers of neutrons. The arrangement and distribution of these subatomic particles determine the overall stability and properties of an atom.

Which subatomic particles are mainly located in the nucleus of an atom? a) Protons and electrons b) Neutrons and electrons c) Protons and neutrons d) Protons, neutrons, and electrons Answer: c) Protons and neutrons

What is the charge of protons? a) Positive b) Negative c) Neutral d) Variable Answer: a) Positive

Where are electrons located in an atom? a) Nucleus b) Energy levels or shells c) Protons d) Neutrons Answer: b) Energy levels or shells

What determines the atomic number of an atom? a) Number of electrons b) Number of protons c) Number of neutrons d) Sum of protons and neutrons Answer: b) Number of protons

What are atoms of the same element with different numbers of neutrons called? a) Isotopes b) Ions c) Elements d) Electrons Answer: a) Isotopes

Hope the information shed above regarding Case Study and Passage Based Questions for Class 9 Science Chapter 4 Structure of Atom with Answers Pdf free download has been useful to an extent. If you have any other queries about CBSE Class 9 Science Structure of Atom Case Study and Passage Based Questions with Answers, feel free to comment below so that we can revert back to us at the earliest possible By Team Study Rate

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myCBSEguide

• Class 9 Science Case...

Class 9 Science Case Study Questions

Table of Contents

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Download the app to get CBSE Sample Papers 2023-24, NCERT Solutions (Revised), Most Important Questions, Previous Year Question Bank, Mock Tests, and Detailed Notes.

If you are wondering how to solve class 9 science case study questions, then myCBSEguide is the best platform to choose. With the help of our well-trained and experienced faculty, we provide solved examples and detailed explanations for the recently added Class 9 Science case study questions.

You can find a wide range of solved case studies on myCBSEguide, covering various topics and concepts. Class 9 Science case studies are designed to help you understand the application of various concepts in real-life situations.

The rationale behind Science

Science is crucial for Class 9 students’ cognitive, emotional, and psychomotor development. It encourages curiosity, inventiveness, objectivity, and aesthetic sense.

In the upper primary stage, students should be given a variety of opportunities to engage with scientific processes such as observing, recording observations, drawing, tabulating, plotting graphs, and so on, whereas in the secondary stage, abstraction and quantitative reasoning should take a more prominent role in science teaching and learning. As a result, the concept of atoms and molecules as matter’s building units, as well as Newton’s law of gravitation, emerges.

Science is important because it allows Class 9 Science students to understand the world around us. It helps to find out how things work and to find solutions to problems at the Class 9 Science level. Science is also a source of enjoyment for many people. It can be a hobby, a career, or a source of intellectual stimulation.

Case study questions in Class 9 Science

The inclusion of case study questions in Class 9 science CBSE is a great way to engage students in critical thinking and problem-solving. By working through real-world scenarios, Class 9 Science students will be better prepared to tackle challenges they may face in their future studies and careers. Class 9 Science Case study questions also promote higher-order thinking skills, such as analysis and synthesis. In addition, case study questions can help to foster creativity and innovation in students. As per the recent pattern of the Class 9 Science examination, a few questions based on case studies/passages will be included in the CBSE Class 9 Science Paper. There will be a paragraph presented, followed by questions based on it.

Examples of Class 9 science class case study questions

Class 9 science case study questions have been prepared by myCBSEguide’s qualified teachers. Class 9 case study questions are meant to evaluate students’ knowledge and comprehension of the material. They are not intended to be difficult, but they will require you to think critically about the material. We hope you find Class 9 science case study questions beneficial and that they assist you in your exam preparation.

The following are a few examples of Class 9 science case study questions.

Class 9 science case study question 1

• due to its high compressibility
• large volumes of a gas can be compressed into a small cylinder
• transported easily
• all of these
• shape, volume
• volume, shape
• shape, size
• size, shape
• the presence of dissolved carbon dioxide in water
• the presence of dissolved oxygen in the water
• the presence of dissolved Nitrogen in the water
• liquid particles move freely
• liquid have greater space between each other
• both (a) and (b)
• none of these
• Only gases behave like fluids
• Gases and solids behave like fluids
• Gases and liquids behave like fluids
• Only liquids are fluids

Answer Key:

• (d) all of these
• (a) shape, volume
• (b) the presence of dissolved oxygen in the water
• (c) both (a) and (b)
• (c) Gases and liquids behave like fluids

Class 9 science case study question 2

• 12/32 times
• 18 g of O 2
• 18 g of CO 2
• 18 g of CH 4
• 1 g of CO 2
• 1 g of CH 4 CH 4
• 2 moles of H2O
• 20 moles of water
• 6.022  ×  1023 molecules of water
• 1.2044  ×  1025 molecules of water
• (I) and (IV)
• (II) and (III)
• (II) and (IV)
• Sulphate molecule
• Ozone molecule
• Phosphorus molecule
• Methane molecule
• (c) 8/3 times
• (d) 18g of CH ​​​​​4
• (c) 1g of H ​​​​​​2
• (d) (II) and (IV)
• (c) phosphorus molecule

Class 9 science case study question 3

• collenchyma
• chlorenchyma
• It performs photosynthesis
• It helps the aquatic plant to float
• It provides mechanical support
• Sclerenchyma
• Collenchyma
• Epithelial tissue
• Parenchyma tissues have intercellular spaces.
• Collenchymatous tissues are irregularly thickened at corners.
• Apical and intercalary meristems are permanent tissues.
• Meristematic tissues, in its early stage, lack vacuoles, muscles
• (I) and (II)
• (III) and (I)
• Transpiration
• Provides mechanical support
• Provides strength to the plant parts
• None of these
• (a) Collenchyma
• (b) help aquatic plant to float
• (b) Sclerenchyma
• (d) Only (III)
• (c) provide strength to plant parts

Cracking Class 9 Science Case Study Questions

There is no one definitive answer to Class 9 Science case study questions. Every case study is unique and will necessitate a unique strategy. There are, nevertheless, certain general guidelines to follow while answering case study questions.

• To begin, double-check that you understand the Class 9 science case study questions. Make sure you understand what is being asked by reading it carefully. If you’re unclear, seek clarification from your teacher or tutor.
• It’s critical to read the Class 9 Science case study material thoroughly once you’ve grasped the question. This will provide you with a thorough understanding of the problem as well as the various potential solutions.
• Brainstorming potential solutions with classmates or other students might also be beneficial. This might provide you with multiple viewpoints on the situation and assist you in determining the best solution.
• Finally, make sure your answer is presented simply and concisely. Make sure you clarify your rationale and back up your claim with evidence.

A look at the Class 9 Science Syllabus

The CBSE class 9 science syllabus provides a strong foundation for students who want to pursue a career in science. The topics are chosen in such a way that they build on the concepts learned in the previous classes and provide a strong foundation for further studies in science. The table below lists the topics covered in the Class 9 Science syllabus of the Central Board of Secondary Education (CBSE). As can be seen, the Class 9 science syllabus is divided into three sections: Physics, Chemistry and Biology. Each section contains a number of topics that Class 9 science students must study during the course.

CBSE Class 9 Science (Code No. 086)

Theme: Materials Unit I: Matter-Nature and Behaviour Definition of matter; solid, liquid and gas; characteristics – shape, volume, density; change of state-melting (absorption of heat), freezing, evaporation (cooling by evaporation), condensation, sublimation. Nature of matter:  Elements, compounds and mixtures. Heterogeneous and homogenous mixtures, colloids and suspensions. Particle nature and their basic units:  Atoms and molecules, Law of constant proportions, Atomic and molecular masses. Mole concept: Relationship of mole to mass of the particles and numbers. Structure of atoms:  Electrons, protons and neutrons, valency, the chemical formula of common compounds. Isotopes and Isobars.

Theme: The World of the Living Unit II: Organization in the Living World Cell – Basic Unit of life:  Cell as a basic unit of life; prokaryotic and eukaryotic cells, multicellular organisms; cell membrane and cell wall, cell organelles and cell inclusions; chloroplast, mitochondria, vacuoles, endoplasmic reticulum, Golgi apparatus; nucleus, chromosomes – basic structure, number. Tissues, Organs, Organ System, Organism: Structure and functions of animal and plant tissues (only four types of tissues in animals; Meristematic and Permanent tissues in plants).

Theme: Moving Things, People and Ideas Unit III: Motion, Force and Work Motion:  Distance and displacement, velocity; uniform and non-uniform motion along a straight line; acceleration, distance-time and velocity-time graphs for uniform motion and uniformly accelerated motion, derivation of equations of motion by graphical method; elementary idea of uniform circular motion. Force and Newton’s laws:  Force and Motion, Newton’s Laws of Motion, Action and Reaction forces, Inertia of a body, Inertia and mass, Momentum, Force and Acceleration. Elementary idea of conservation of Momentum. Gravitation:  Gravitation; Universal Law of Gravitation, Force of Gravitation of the earth (gravity), Acceleration due to Gravity; Mass and Weight; Free fall. Floatation:  Thrust and Pressure. Archimedes’ Principle; Buoyancy. Work, energy and power:  Work done by a Force, Energy, power; Kinetic and Potential energy; Law of conservation of energy. Sound:  Nature of sound and its propagation in various media, speed of sound, range of hearing in humans; ultrasound; reflection of sound; echo.

Theme: Food Unit IV: Food Production Plant and animal breeding and selection for quality improvement and management; Use of fertilizers and manures; Protection from pests and diseases; Organic farming.

PRESCRIBED BOOKS:

• Science-Textbook for class IX-NCERT Publication
• Assessment of Practical Skills in Science-Class IX – CBSE Publication
• Laboratory Manual-Science-Class IX, NCERT Publication
• Exemplar Problems Class IX – NCERT Publication

myCBSEguide: A true helper

There are numerous advantages to using myCBSEguide to achieve the highest results in Class 9 Science.

• myCBSEguide offers high-quality study materials that cover all of the topics in the Class 9 Science curriculum.
• myCBSEguide provides practice questions and mock examinations to assist students in the best possible preparation for their exams.
• On our myCBSEguide app, you’ll find a variety of solved Class 9 Science case study questions covering a variety of topics and concepts. These case studies are intended to help you understand how certain principles are applied in real-world settings
• myCBSEguide is that the study material and practice problems are developed by a team of specialists who are always accessible to assist students with any questions they may have. As a result, students may be confident that they will receive the finest possible assistance and support when studying for their exams.

So, if you’re seeking the most effective strategy to study for your Class 9 Science examinations, myCBSEguide is the place to go!

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Extra Questions for Class 9 Science Chapter 4 Structure of the Atom

Extra questions for Class 9 Science Chapter 4 Structure of the Atom with answers is given below. Our subject expert prepared these solutions as per the latest NCERT textbook. These questions will be helpful to revise the all topics and concepts. CBSE Class 9 extra questions are the most simple and conceptual questions that are prepared by subject experts for the students to study well for the final exams. By solving these extra questions, students can be very efficient in their exam preparations.

Structure of the Atom Class 9 Science Extra Questions and Answers

Very short answer questions.

1: Draw the atomic structure of hydrogen atom. Answer:

2: Why are some elements chemically inert? Answer:  Because their outermost shell is completely filled.

3: Why is atom electrically neutral? Answer:  It has same number of protons and electrons, (positive charge = negative charge).

4: What is the charge and mass of a-particles? Answer:  Charge is + 2 Mass is 4 a.m.u.

5: What are valence electrons? Answer:  Electrons present in the outermost shell of an atom are called valence electrons.

6: An atom has atomic number 12, what is its valency and name the element? Answer:  Atomic number = 12 ∴ Protons = Electrons = 12 Electrons Configuration = K L M -2 8 2 ∴ Valency = 2 Element is magnesium.

7: Find the number of neutrons in  27 13 X. Answer:  Mass number = 27 ∴ p + n = 27 p = 13, (Atomic No. = Number of protons) ∴ 13 + n = 27 ∴ n = 14 ∴ Neutron =14

8: Where is the mass of atom is concentrated? Answer:  Mass of an atom is concentrated in nucleus.

9: Name two elements with same number of protons and neutrons? Answer:  Carbon (Protons = Neutrons = 6) Oxygen (Protons = Neutrons = 8)

10: Draw the atomic structure of sodium atom. Answer: 

11: Name the isotope used for treatment of cancer. Answer:  Isotope of cobalt. 12: AZX What does this symbol represent? Answer:  X → Symbol of element A → Mass number Z → Atomic number

13: Can the value of ‘Z’ be same for two different atoms? Answer:  No, (Z = atomic number), two different atoms cannot have same atomic number.

14: Can the value of A’ be same for two different atom? Answer:  Yes, it can be e.g. Ca and Ar has A-40 (i.e., mass number).

Short Answer Type Questions

1: Name the scientist who discovered protons and neutrons in an atoms. Answer:  Protons were discovered by E. Goldstein in 1866 and neutrons were discovered by J, Chadwick in 1932.

2: What is the contribution of Bohr and Bury together in the structure of atom’s explanation? Answer:  Both Bohr and Bury gave the distribution of electrons into different atoms by giving the formula 2n 2 , where n = shell number.

3: Draw the atomic structure of (i) an atom with same number of sub-atomic particles, (ii) an atom with same number of electrons in L and M shell.

Answer:  (i) An atom with same number of sub-atomic particles is He No. of protons = 2 No. of electrons = 2 No. of neutrons = 2

(ii) An atom with L and M shell filled → K L M- 2 8 8

4: What is an octate? Why would atoms want to complete their octate?

Answer:  When the outermost shell of an atom i.e., L, M or N are completely filled with 8 electrons in the shell, it is said an octate. Atoms would want to complete their octate because they want to become stable. 

5: Find the valency of  14 7 N and  35 17 Cl.

Answer:  The atomic number of nitrogen = 7, No. of protons = 7, No. of electrons = 7 Electronic configuration = K L M = 2 5 – Valency = 3 Because either it will gain three electrons or share 3 electrons to complete its octate. The atomic number of chlorine = 17, p = 17, e=17 Electronic configuration = K L M= 2 8 7 Valency = 1 Because it will gain 1 electron to complete its octate. 

8: What are nucleons? What is the name given to those atoms which have same number of nucleons in it?

Answer:  Protons and neutrons present in the nucleus are called nucleons Isobaric elements have same number of nucleons in it.

9: Give the difference between three sub-atomic particles.

Answer:  Three sub-atomic particles are electron, proton and neutron

10. Give the names of three atomic species of hydrogen. Answer:  Three atomic species of hydrogen are:

11: Atomic Mass exists as whole number, why do we write the atomic mass of chlorine as 35.5 u.

Answer:  Chlorine has two isotopes and the mass of an atom is taken as the average mass of all the naturally occurring atoms of that element. This is obtained by knowing the percentage of each isotopic from and then the average mass is calculated Cl = 35 – 75% and Cl = 37 – 25% = 35.5 u

12:  Give difference between isotopes, and isobars. Answer:

13: Number of protons and electrons are same in an atom. Then why is it wrong to say that atomic number of an atom is equal to its number of electrons.

Answer:  Atomic number ≠ Number of electrons, although number of protons = number of electrons because the electron’s number can change in an atom by loss, or gain of it. But the proton’s number remain constant (as it does not take part in loss or gain). 14: An atom is electrically neutral, on loss or gain of electrons why does it become charged?

Answer:  An atom is electrically neutral because of same number of protons and electrons. But it becomes charged, to become stable atom, loses or gains electrons. Hence, Number of protons ≠ Number of electrons If it loses electrons p > e; hence +ve charge is obtained. If it gains electrons e > p; hence -ve charge is obtained. 15: What is valency? Explain different types of valencies. Answer:  The combining capacity of an atom is called its valency. There are 2 types of valencies.

Some atoms also show zero valency when there outermost shell is completely filled. 16:  With the help of an activity in daily life, how can you prove that atoms are divisible. 

Answer:   Activity

• Take a scale, rub it on hair, try to attract a small bit of paper.
• Now divide the bit of paper further into smaller pieces
• Again bring the charged scale near to this pieces of papers.
• You will observe that the bits of paper still get attracted.

Conclusion:  This activity shows that atom contains charges and these charges are opposite in nature which shows the attraction. Hence here scale and paper both are oppositely charged and hence attract each other. Also, every atom has at least one sub-atomic particle.

17: In the structure of an atom why are protons present in the centre and are not pulled outside by the electrons as both are oppositely charged with same unit of charge?

Answer:  Protons are heavy with mass 1 unit and hence are concentrated in the centre   of the atom. The mass of electrons is negligible i.e.1/1800 times less than that of protons. Hence are not able to attract the protons and pull them out of the nucleus, although their charge is of same value. 

18: According to you, among the structure of atom studied which model is correct and why?

Answer:  Bohr’s model of an atom is the best model and is correct because it gives the explanation of nucleons (protons and neutrons) in the centre and how electrons revolve around the nucleons in their discrete, special orbits, so electrons don’t loose/radiate energy and remain bonded in their shell. 

Long Answer Type Questions

1. Give an activity to understand the implications of Rutherford’s a scattering experiment by a gold foil.

Answer:  To understand the implications of Rutherford’s a-particle scattering experiment: Activity:  Let a child stand in front of a wall with his eyes closed. Let him throw stones at the wall from a distance. He will hear sound for each strike of stone on the wall. This is like a nucleus of the atom. But if a blind-folded child has to throw stones at a barbed-wire fence, most of the stones would not hit the fencing and no sound would be heard. This is because there are lots of gap in the fence which allows the stone to pass through them. This is like empty space in an atom through which a-particles will pass through. Based on the above activity and similar reasoning Rutherford concluded the a-particle scattering experiment as: (1) Most of the space inside the atom is empty as a-particles passed through the foil. (2) Very few particles deflected from their path, this show that positive charge occupies less space. (3) A very small fraction of a-particles are deflected by 180°, this shows that all the positive charge and mass of the gold atom were concentrated in a very small volume within the atom.

2: What are isotopes? State its characteristics, give uses of isotopes?

Answer:  Atoms of same element with same atomic number but different mass number are isotopes. Characteristics:  (1) Physical properties of the isotopes are different e.g. mass, density. (2) Chemical properties of the isotopes are same due to same number of electrons. Uses: (1) Uranium isotope is used as a fuel in nuclear reactor (U-235). (2) Cobalt isotope is used for treatment of cancer (Co-60). (3) Iodine isotope is used in the treatment of goitre.

3: Explain Rutherford’s α-particle scattering experiment and give its observation and conclusion drawn.

Answer:   Rutherford’s α-particle scattering experiment: Fast moving α-particles were made to fall on a thin gold foil. Particles have + 2 charge and 4u mass, and considerable amount of energy.

Observations: (1) Most of the α-particles passed straight through the foil. (2) Some of the α-particles were deflected by small angles by the foil. (3) One out of every 12000 particles rebounded.

Conclusion from observation: (1) Most of the space inside the foil is empty. (2) Positive charge of atom occupies very less space. (3) Mass of the atom is concentrated in the centre with all positive charge concentrated in small volume within the atom.

4: Establish the relationship between atomic number, mass number, isotopes, isobars and valency of an atom.

Answer:  Atomic number — Gives the number of protons (Z) Mass number — Gives the number of protons and neutrons (A) Isotopes — When atoms of same element have same number of protons (Z) but different number of a neutrons (s) such atoms are called isotopes. Isobars — When atom of different element have same mass number (A) but different atomic number (Z) such atoms are called isobars. Valency — It is the combining capacity of an atom.

Value Based Questions

1: Aryan could not solve the following question in the group; his group mate explained him and solved his difficulty. The question was as follows: What information do you get from the given figure about the atomic number, mass number and valency of the given atom X’. (a) What is the answer for-the above question? (b) Name the element X’. (c) What value of Aryan’s friend is reflected in this behaviour?

Answer:  (a) The atomic number is 5. The mass number is 11. The valency is 3. (b) The element X’ is boron. (c) Aryan’s friend showed the value of helping and caring nature.

CBSE Case Study Questions for Class 9 Science - Pdf PDF Download

Cbse case study questions for class 9 science.

Case based questions for Class 9 Science involve exploring a real-world situation through scientific analysis and inquiry. These questions allow students to make connections between science concepts and the world around them, as well as develop critical thinking skills. For example, a case study may involve challenging a student to determine the cause of an illness in a local population by researching the disease, its symptoms, and the local environment. Through this exercise, students learn how to identify a problem, break it down into parts, and come up with a solution that is supported by evidence. This type of question helps students to understand how science is at the centre of solving real-world problems.

Chapter Wise Case Based Questions for Class 9 Science

Chapter-wise case-based questions for Class 9 Science are a set of questions based on specific chapters or topics covered in the science textbook. These questions are designed to help students apply their understanding of scientific concepts to real-world situations and events.

The CBSE Class 9 Case Based Questions can be accessed from Chapetrwise Links provided below:

Chapter 1: Matter In Our Surroundings

Chapter 2: is matter around us pure.

• Case Based Questions: Is Matter Around Us Pure?

Chapter 3: Atoms And Molecules

• Case Based Questions: Atoms And Molecules

Chapter 4: Structure Of The Atom

• Case Based Questions: Structure Of The Atom

Chapter 5: The Fundamental Unit Of Life

• Case Based Questions: The Fundamental Unit Of Life- 1
• Case Based Questions: The Fundamental Unit Of Life- 2

Chapter 6: Tissues

• Case Based Questions: Tissues- 1
• Case Based Questions: Tissues- 2

Chapter 7: Motion

• Case Based Questions: Motion-1 
• Case Based Questions: Motion- 2

Chapter 8: Force And Laws Of Motion

• Case Based Questions: Force And Laws Of Motion

Chapter 9: Gravitation

• Case Based Questions: Gravitation

Chapter 10: Work And Energy

• Case Based Questions: Work And Energy- 1
• Case Based Questions: Work And Energy- 2

Chapter 11: Diversity In Living Organisms

Chapter 12: sound, chapter 13: natural resources, chapter 14: improvement in food resource, chapter 15: why do we fall ill.

• Case Based Questions: Why Do We Fall Ill?

Weightage of Case Based Questions in Class 9 Science

Why are Case Study Questions important in Science Class  9?

• Enhance critical thinking:  Case study questions require students to analyze a real-life scenario and think critically to identify the problem and come up with possible solutions. This enhances their critical thinking and problem-solving skills.
• Apply theoretical concepts:  Case study questions allow students to apply theoretical concepts that they have learned in the classroom to real-life situations. This helps them to understand the practical application of the concepts and reinforces their learning.
• Develop decision-making skills:  Case study questions challenge students to make decisions based on the information provided in the scenario. This helps them to develop their decision-making skills and learn how to make informed decisions.
• Improve communication skills:  Case study questions often require students to present their findings and recommendations in written or oral form. This helps them to improve their communication skills and learn how to present their ideas effectively.
• Enhance teamwork skills:  Case study questions can also be done in groups, which helps students to develop teamwork skills and learn how to work collaboratively to solve problems.

In summary, case study questions are important in Class 9 because they enhance critical thinking, apply theoretical concepts, develop decision-making skills, improve communication skills, and enhance teamwork skills. They provide a practical and engaging way for students to learn and apply their knowledge and skills to real-life situations.

Class 9 Science Curriculum at Glance

The Class 9 Science curriculum in India covers a wide range of topics and concepts. Here is a brief overview of the Science curriculum at a glance:

• Physics:  The Physics section includes topics such as motion, force, work and energy, sound, and light.
• Chemistry:  The Chemistry section includes topics such as matter, atoms and molecules, structure of the atom, and chemical reactions.
• Biology:  The Biology section includes topics such as cell structure and functions, tissues, diversity in living organisms, natural resources, and environmental management.
• Practical Work:  The Science curriculum also includes practical work, where students perform experiments to observe and understand scientific phenomena.

The Class 9 Science curriculum is designed to provide a strong foundation in science and prepare students for higher education in the field. The curriculum is structured to develop critical thinking, problem-solving, and analytical skills, and to promote the application of scientific concepts in real-life situations. The curriculum is also designed to help students prepare for competitive exams and develop a strong scientific base for future academic and professional pursuits.

Students can also access Case Based Questions of all subjects of CBSE Class 9

• Case Based Questions for Class 9 Maths
• Case Based Questions for Class 9 Social Science
• Case Based Questions for Class 9 English
• Case Based Questions for Class 9 Hindi
• Case Based Questions for Class 9 Sanskrit

Frequently Asked Questions (FAQs) on Case Based Questions for Class 9 Science

Are case-based questions on the class 9 science exam.

Yes, case-based questions are often included in science exams at the class 9 level as they test students' ability to apply their scientific knowledge and skills to real-world situations.

How are case-based questions different from traditional science questions?

Traditional science questions typically focus on testing students' knowledge of specific facts, concepts, and theories. Case-based questions, on the other hand, require students to use their knowledge and understanding to analyze and interpret real-world situations and make informed decisions.

How can students prepare for case-based questions in science?

To prepare for case-based questions in science, students should practice analyzing data and interpreting scientific experiments. They should also work on developing their critical thinking and problem-solving skills.

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• Important Questions For Class 9 Science

CBSE Important Questions for Class 9 Science

CBSE Important Questions for Class 9 Science play an important role in students’ exam preparation. It gives an idea of what types of questions can be asked in the examination. It also develops skills for miscellaneous questions, which are generally neglected by students. Moreover, practising CBSE Important Questions for Class 9 Science will boost the student’s confidence.

By solving these important questions, the students will be more familiar with the type of questions asked in final exams. Hence, they will be able to face the exams more confidently and without fear. Science is a subject which needs conceptual understanding. Just mugging up the answer will not fulfil the purpose. While solving the CBSE Class 9 important questions of Science, students will easily grasp the concepts. Apart from this, they will also acquire answer writing skills in a better way. They will learn to draw the diagrams and write the formulas wherever it is required while answering. This will help them fetch more marks in exams.

Students must start solving the important questions once they complete the CBSE Class 9 Science Syllabus at least 2 months before the annual exam. Here, we have provided the chapter-wise CBSE important questions for Class 9 Science. These questions are created from an exam perspective and are most likely to be asked in the exam.

CBSE Class 9 Science Marking Scheme

The table below shows the weightage of the types of questions asked in the exam. Go through it to know the Class 9 Science Exam pattern in detail. We have included all these types of questions in the CBSE Important Questions so that students do not miss anything.

Benefits of Important Questions for CBSE Class 9 Science

CBSE Important Questions for Class 9 Science gives a competitive edge to the students. Here are the benefits of studying through these important questions:

• Students will revise everything and cover the entire syllabus.
• The questions are created by the subject experts exclusively for students to prepare better for the exams.
• There is a high chance that some of these questions will be asked in the exam.
• Students will have good practice with different types of questions and will be well prepared for the Science paper.

We hope students have found this information on “CBSE Important Question for Class 9 Science” useful for their studies. Students can also access CBSE Class 9 Science Sample Papers , solutions, exam tips, projects, etc., on BYJU’S website.

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Case Study Questions for Class 9 Science Chapter 1 Matter in Our Surroundings

• Last modified on: 3 days ago
• Reading Time: 6 Minutes

Here we are providing case study questions for class 9 science chapter 12 sound. Students are suggested to go through each and every case study questions for better understanding of the chapter.

Case Study/Passage Based Questions:

Question 1:

Read the following passage and answer the questions given below.

Every matter is made up of tiny particles. These particles are so tiny that they can’t be seen with naked eyes.

The three characteristics shown by particles of matter are as follows:

(i) There are small voids between particles in a matter. This characteristic is the concept behind the solubility of a substance in other substances.

(ii) Particles of matter show continuous random movements, that is they possess kinetic energy. The spreading of ink in a beaker of glass, smell of agarbattis, etc. are few illustrations that show the movement of particles of a substance.

(iii) The particles of matter attract each other with a force called interparticle force of attraction. Read the given passage carefully and give the answer of the following questions:

Q 1. Spreading of fragrance of a burning incense stick in a room shows that:

a. particles of matter have spaces between them.

b. particles of matter attract each other.

c. particles of matter are constantly moving.

d. None of the above

Q 2. What happens when we add sugar to water?

a. Volume of water doubles.

b. Volume of water decreases

c. Volume of water remains the same.

Q 3. A stream of water cannot be cut by fingers. Which property of matter does this observation show?

a. Particles of matter attract each other.

b. Particles of matter have spaces between them.

c. Particles of matter are continuously moving.

Q 4. When we put some crystals of potassium permanganate in a beaker containing water, we observe that after some time, the whole water turns pink. This intermixing of particles of two different types of matter on their own is called:

a. Brownian motion

c. sublimation

d. diffusion

Q 5. Why is the rate of diffusion of liquids higher than that of solids?

a. In the liquid state, particles are tightly packed as compared to solids.

b. In the liquid state, particles move freely as compared to solids.

c. In solid state, particles have least force of attraction between the particles.

d. In solid state, particles cannot be compressed easily.

• (c) particles of matter are constantly moving.
• (c) Volume of water remains the same.
• (a) Particles of matter attract each other.
• (d) diffusion
• (b) In the liquid state, particles move freely as compared to solids

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Case Study Questions Class 9 Science Work and Energy

Case study questions class 9 science chapter 11 work and energy.

CBSE Class 9 Case Study Questions Science Work and Energy. Important Case Study Questions for Class 9 Exam. Here we have arranged some Important Case Base Questions for students who are searching for Paragraph Based Questions Work and Energy.

At Case Study Questions there will given a Paragraph. In where some Questions will made on that respective Case Based Study. There will various types of marks will given 1 marks, 2 marks, 3 marks or 4 marks.

CBSE Case Study Questions Class 9 Science – Work and Energy

(1 ) Work done by force acting on an object is equal to the magnitude of the force multiplied by the distance moved in the direction of the force. Work has only magnitude and no direction. Work done is negative when the force acts opposite to the direction of displacement. Work done is positive when the force is in the direction of displacement.The unit of work is newton-metre (N m)or joule (J).

(i) Work done is

(a) Scalar quantity

(b) Vector quantity

(c) Tensor quantity

(d) None of these

(ii) When force acts against the direction of displacement then work done will be

(a) positive

(b) negative

(c) both a and b can possible

(iii) SI unit of work is

(a) Joule(J)

(b) Newton meter(N-m)

(c) both a and b

(iv)You are lifting stone from floor. Work is done by theforce exerted by you on the stone. Theobject moves upwards. The force youexerted is in the direction ofdisplacement. However, there is theforce of gravity acting on the object. Which one of these forces is doingpositive work?

 Which one is doing negative work?

(v) Define 1J of work.

Answer key-1

(iv) Here work done by you is positive work as work is being done in the direction of displacement unlike in case of gravitational force which acts in downward direction against the direction of displacement which is in upward direction.

(v) When 1 Newton of force acts on body and body displaces from its position by 1 meter then the work done is said to be 1 joule (J).

(2) A moving object can do work. An object moving faster can do more work than an identical object moving relatively slow. A moving bullet, blowing wind, a rotating wheel, a speeding stone can do work. How does a bullet pierce the target? How does the wind move the blades of a windmill? Objects in motion possess energy. We call this energy kinetic energy.

Thus, the kinetic energy possessed by an object of mass, m and moving with a uniform velocity, v is

KE = ½ *mv 2

The energy possessed by an object is thus measured in terms of its capacity of doing work. The unit of energy is, therefore, the same as that of work, that is, joule (J).

(i) Energy possessed by body which is in motion is called

(a) Potential energy

(b) Kinetic energy

(c) Nuclear energy

(ii) Which of the following has same unit?

(a) Potential energy and Force

(b) Kinetic energy and work

(c) Both a and b

(iii) Kinetic energy depends

(a) Inversely on velocity of body

(b) Directly on square of velocity of body

(c) Directly on  velocity of body

(iv) Define kinetic energy of body. Give its SI unit

(v) Is kinetic energy scalar or vector? Justify your answer

Answer key-2

(iv) Energy possessed by object due to its motion is called as kinetic energy. Its SI unit is N-m or Joule(J).

(v) kinetic energy is scalar quantity as it is a work done and work done is scalar quantity hence kinetic energy is also scalar quantity and doesn’t have any direction.

(3) Lift an object through a certain height. The object can now do work. It begins to fall when released. This implies that it has acquired some energy. If raised to a greater height it can do more work and hence possesses more energy. From where did it get the energy? In the above situations, the energy gets stored due to the work done on the object. The energy transferred to an object is storedas potential energy if it is not used to cause a change in the velocity or speed of the object.An object increases its energy when raisedthrough a height. This is because work isdone on it against gravity while it is being raised. The energy present in such an objectis the gravitational potential energy.The gravitational potential energy of anobject at a point above the ground is definedas the work done in raising it from the ground by height h

to that point against gravity.Let the work done on the object against gravity beW. That is,

work done, W = force × displacement

Therefore potential energy (PE)= mg*h.

(i) Energy possessed by body due to its position is called

(ii) SI unit of potential energy is

(iii)You do work while winding the key of a toy car. The energy transferred to the spring inside is stored as

(iv)Find the energy possessed by an object of mass 5kg when it is at a height of 10 m above the ground. Given, g = 9.8 m/s 2 .

(v)Find the work done by Gravity on an object of mass 5 kg which moves from height 10m to ground when it is released from height of 10 m. Given, g = 9.8 m/s 2 .

Answer key-3

(iv) we have potential energy as

=5 ×9.8 ×10

(v) work done, W = force × displacement

= 5 ×9.8 ×10

(4) The form of energy can be changed from one form to another. What happens to the totalenergy of a system during or after the process?Whenever energy gets transformed, the totalenergy remains unchanged. This is the law ofconservation of energy. According to this law, energy can only be converted from one form to another it can neither be created nor destroyed. The total energy before and after the transformation remains the same.The lawof conservation of energy is valid inall situations and for all kinds of transformations. Thus during motion the sum of the potential energy and kinetic energy of the object would be the same at all points. That is, potential energy + kinetic energy = constant.Andcalled as mechanical energy.

(i) Which of the energy conversion occur in electric iron?

(a) Electric energy converted into heat energy

(b) Electric energy converted into light energy

(c) Heat energy converted into electrical energy

(ii) When ball drops from height which of the energy conversion takes place

(a) Gravitational potential energy converted into kinetic energy

(b) Kinetic energy converted into Gravitational potential  energy

(iii) When ball is thrown vertically upward which of the following quantity remains constant?

(c) Potential energy

(iv) State law of conservation of energy.

(v) In hydroelectric power plant which energy conversion happens?

Answer key-4

(iv) This is the law ofconservation of energy. According to this law,energy can only be converted from one form to another it can neither be created nor destroyed. The total energy before and after the transformation remains the same.

(v)  In hydroelectric power plant potential energy of water reservoir is converted into electric energy.

(5 ) A more powerful vehiclewould complete a journey in a shorter timethan a less powerful one. We talk of the powerof machines like motorbikes and motorcars.The speed with which these vehicles changeenergy or do work is a basis for theirclassification. Power measures the speed ofwork done, that is, how fast or slow work isdone. Power is defined as the rate of doingwork or the rate of transfer of energy. If anagent does a work W in time t, then power isgiven by

P= work/time

P= W/T. The unit of power is watt.

(i) The rate of doing work is defined as

(ii) Total energy consumed divided by total time taken is called as

(a) Average power

(b) Instantaneous power

(iii) Let A and B having same weight start climbing the rope and reach height of 10m. Let A takes 10sec while B takes 12sec then work done

(a) By both will be same

(b) By A is more than work done by B

(c) By B is more than work done by A

(iv) Define 1 Watt of power

(v) An electric bulb of 20W is used for 5h per day. Calculate the ‘units’ of energy consumed in one day by the bulb.

Answer key-5

(iv) A power is said to be 1 watt when 1 joule of work is done within 1 second of time.

(v) Power of electric bulb = 20 W

Time used, t = 5 h

Energy = power × time taken

= 0.02kW × 5 h

= 0.10 kW h

= 0.10‘units’.

The energy consumed by the bulb 0.10 units

Jaru mitaya

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