CBSE Class 9 Science Lab Manual PDF Free Download

CBSE Class 9 Science Lab Manual PDF Download Info

Class 9 Cbse Science Practical Is Equally Important As The Theoretical Subject. Students Learn From Practicals And These Learning Will Stay In Their Memory For A Longer Time. Most Of The Students Usually Forget The Concepts They Have Learned In Theory Classes.

CBSE Class 9 Science Lab Manual PDF Free Download

However, After Completion Of The Science Practical, Students Remember The Things For A Longer Time. What We See Gets Permanently Etched In Our Memory, But What We Listen To Does Not Stick Around For Too Long In Our Head. This, The Cbse Board Modified The In-class 9 Science Classes To Include Practicals.

In This, We Have Provided All The Knowledge Pupils Need To Be Able To Complete Their Class 9 Science Cbse Practicals.

Exercises Related To Science Not Only Help Children In Their Conceptual Understanding But Also Develop Their Interest. They Get A Platform To Represent Their Ideas And Practice New Things. In This Way, Their Interest In Science Is Also Boosted. Moreover, Students Who Fear Science Also Begin To Take Interest In The Subject.

Now, let us consider each question in detail:

1. How to write a scientific laboratory handbook?

To write a scientific laboratory handbook one needs to carry out orderly arrangements of the experiments, their simplification, and their proper record. The essential steps involved are basically:

• Title and Objective: Clearly mention the title and objective of the experiment.
• Materials Needed: What materials and instruments will be needed to carry on with this experiment?.
• Procedure: Add a step-by-step explanation to make experiments reproducible or executable by everybody.
  Observations and Data: Leave spaces for observations and data to be recorded in tabular, diagrammatic forms, or any other presently used graphical representation.
• Analysis and computations: Include, where relevant, sections treating data analyses or particular computations.
• Conclusion: Present an overall summary of the finding, state them, and discuss their implications.
  Precations: Mention precautions that should be taken.

Ensure that every section of the handbook is clearly headed and sub-headed and easy to navigate through.

2. What is the syllabus of Science for CBSE Class 9?

Given below are the broad topics mostly covered under the CBSE Class 9 Science syllabus:

Physics:

Matter: its nature and behaviour – Atoms and molecules

Atomic structure – Chemical reactions

Periodic classification of elements

Biology: Tissues; The basic building block of life; Diversity in living things

Laws of motion and force in motion

Natural resources, work and energy, sound, gravitation, and This broad syllabus seeks to introduce fundamental concepts in biology, chemistry and physics.

3. What is the proper way of Approaching Science in Class 9 CBSE?

Following are some effective methods to study science in Class 9 CBSE:

• Syllabus Awareness: Familiarize oneself with the topics and subtopics that make up the syllabus.
• Chalking out a Study Schedule: Allot specific times for studying each subject.
• Texts and Resources: NCERT texts, being based on the CBSE pattern of teaching, may be referred to.
• Note making: Learn with brief notes to help in understanding and revision.
• Practice from past Years’ Papers: Solve past years’ question papers to get an idea about the test trends and the type of questions asked. Question any doubts: Elucidate doubts, if any, at the right time with professors or friends.
• Keep revising: Frequent revision grips one up on the subject matters and helps in retention.
   

4. Is science tough in class nine?

The science 9th class is difficult for some classes, whereas not for others. It all depends on the interest, previous knowledge, and study habits of different students.

For many students, it serves as a stepping stone to advanced concepts in biology, chemistry, and physics. If students at large practice, study, and understand the basic topics, the class 9 Science may not be so tough and may even be enjoyable.

Ultimately, how tough an issue seems to study can be drastically tilted by how curiously one approaches it, how diligently one studies over it, and whether or not one asks for help when he needs it.

Important Questions for Science Practical in CBSE Class 9

Here are some of the questions from CBSE Class 9 Science textbooks. This includes some of the questions from science themes of chemistry, biology and physics. Though these are all also accessible to the students in the PDF files linked above. Moreover, a few questions are also mentioned at the end of each experiment in the lab manual.

Q1) A 100 g block slides when tension in the string is x N. What will be the tension in the string when an identical block is placed at the top of the first block?

When an identical block is placed on top of the first block, the total mass that the tension in the string needs to support becomes 200 g (since each block is 100 g). The tension in the string ( T ) can be calculated using Newton’s second law:

[ T – mg = ma ]

where ( m ) is the total mass (200 g = 0.2 kg), ( g ) is the acceleration due to gravity (approximately 9.8 m/s²), and ( a ) is the acceleration of the blocks (assuming they move together).

Since the blocks slide together, ( a ) is zero (they move with constant velocity). Therefore,

[ T = mg = 0.2 \times 9.8 = 1.96 \text{ N} ]

So, the tension in the string when the second block is placed on top will be 1.96 N.

Q2) State the factors on which the buoyant force acting on an object immersed in a fluid depends.

The buoyant force ( F_b ) acting on an object immersed in a fluid depends on:

• Volume of the displaced fluid: The buoyant force is equal to the weight of the fluid displaced by the object.
• Density of the fluid: Buoyant force increases with the density of the fluid.
• Acceleration due to gravity: Higher gravity results in a higher buoyant force.

Q3) What will happen if a de-shelled egg is placed in a solution with the same osmotic concentration as in the egg?

If a de-shelled egg (bare membrane) is placed in a solution with the same osmotic concentration (isotonic solution) as inside the egg, there will be no net movement of water molecules across the egg membrane. This means:

• The egg membrane will neither shrink (due to water leaving the egg) nor swell (due to water entering the egg).
• The egg will remain in its current state without any change in size.

Q4) What are the conditions that are helpful for the breeding of mosquitoes?

Mosquitoes breed in stagnant water bodies where the following conditions are favorable:

• Stagnant Water: Mosquitoes lay their eggs in stagnant or slow-moving water.
• Warm Temperature: Warmer temperatures accelerate the growth and development of mosquito larvae.
• Presence of Organic Matter: Organic matter in water bodies provides nutrients for mosquito larvae.
• Sheltered Areas: Mosquitoes prefer shaded and protected areas for breeding.
• Absence of Predators: Lack of natural predators allows mosquito larvae to thrive.

Q5) A metal cylinder is melted, and the whole mass is cast in the shape of a cube. What happens to its density? Give reasons.

When a metal cylinder is melted and then cast into the shape of a cube, the volume of the metal remains the same before and after melting (assuming no loss). However, the shape changes from a cylinder (which has a different surface area to volume ratio compared to a cube).

Density ( \rho ) is defined as ( \rho = \frac{m}{V} ), where ( m ) is mass and ( V ) is volume.

Since mass ( m ) remains the same and volume ( V ) remains the same (as per the conservation of mass and volume principle),

[ \rho = \frac{m}{V} ]

Therefore, the density of the metal remains unchanged after melting and reshaping.

Q6) What different techniques of separation can be employed for the separation of components of a homogeneous and heterogeneous mixture?

For homogeneous mixtures (like solutions):

• Distillation: Separates liquids based on differences in boiling points.
• Filtration: Separates solids from liquids or gases by passing through a filter.
• Evaporation: Separates a solvent from a solution by evaporating the solvent.

For heterogeneous mixtures (like suspensions or colloid solutions):

• Filtration: Separates solids from liquids using a filter.
• Centrifugation: Separates components based on differences in density.
• Decantation: Separates liquid from solid precipitates by pouring off the liquid.
• Magnetic Separation: Uses magnets to separate magnetic materials from non-magnetic ones.

Each technique exploits physical properties such as particle size, density, magnetic susceptibility, and volatility to achieve separation.