CBSE Revision Notes

The Fundamental Unit Of Life Class 9 CBSE Notes – Chapter 5

What are Living Organisms Made Up of?
These cells contain many structures called organelles that perform various roles which help the cell to sustain itself. The common cell organelles are:

1. Nucleus
2. Cell wall
3. Cytoplasm
4. Endoplasmic reticulum
5. Golgi apparatus
6. Lysosomes
7. Mitochondria
8. Plastids
9. Vacuoles

However, certain cell organelles are specific to certain cells. For instance, cell walls and vacuoles are exclusive to plant cells. Lysosomes are seen only in animal cells, but they perform similar functions as vacuoles in plant cells.

Structure Of The Atom Class 9 CBSE Notes – Chapter 4

Essentially, the structure of an atom comprises of protons, neutrons and electrons. These basic components provide the mass and charge of the atoms. The nucleus comprises of proton and neutron, with the electron orbiting around that.

The Structure of an Atom:
Over the years, many models of atoms have been put forth based on theories and assumptions. But one of the many significant models includes the Bohr Model, Thomson’s Model and Rutherford’s Model. However, these are quite outdated today. The Bohr-Sommerfeld Theory is the most widely accepted model that explains the atomic structure. In this model, the concept of electrons revolving around orbits are completely scrapped, instead, electrons exist in “energy states.” Please refer  Structure of the Atom Class 9 Notes for more revision notes.

Atoms And Molecules Class 9 Notes – Chapter 3

Atoms and molecules are responsible for forming tiny sand particles, gargantuan black holes and everything in between. The atom is the most fundamental unit of matter, making up everything that we see around us. It is extremely small, measuring in at less than 0.1 to 0.5 nanometers. Please refer Atoms and Molecules Class 9 Notes for more revision notes.

Is Matter Around Us Pure Class 9 Notes – Chapter 2

We do know that matter is made up of particles which are arranged in a certain way. Gases particles are well separated and can freely move about, solids, on the other hand, have particles that are tightly packed, usually with no scope to move around. Please refer Is Matter Around Us Pure Class 9 Notes for more revision notes.

Matter In Our Surroundings Class 9 Notes – Chapter 1

Everything that we see around us is made up of matter. Even the air that we breathe is made up of matter. But what exactly is matter, and is everything really made up of matter?

Physical Nature of Matter:
Abstract concepts like memories, thoughts are not considered a matter because they do not occupy any physical dimension or space. Essentially, the matter in our surroundings from sand, trees, building and even the air has a certain mass and occupies space. This characteristic feature of taking up space and having a mass constitutes matter. Please refer Matter in Our Surroundings Class 9 Notes for more revision notes.

Probability Class 9 Notes – Chapter 15

We can define probability as the measure of the likelihood that an event will occur. We can calculate the probability of a single event occurring by dividing the number of events by the number of possible outcomes. Probability Class 9 Notes are provided here to help students understand the concept of this topic more effectively.

Statistics Class 9 Notes: Chapter 14

Statistics Class 9 Notes are the premier study tool that will help students get a complete overview of chapter 14 given in the CBSE math textbook. The note provided here have been designed to offer a clear understanding of the concepts as well as helps students study effectively. Some of the important topics covered in chapter 14 notes include;

• What is statistics
• Collection of Data
• Presentation of Data
• Measures of Central Tendency
• Important Questions

Surface Area and Volume Class 9 Notes: Chapter 13

Surface Areas and Volumes Class 9 Notes contain detailed and accurate information that will enable students to get a good grip on the concepts discussed in chapter 13 of the maths textbook. Students will also get a glimpse of the important questions and once they get familiar with the notes they will significantly increase their chances of scoring higher marks in the exams. To give you a brief outlook of Chapter 12 notes, it deals with topics like;

• What is Surface Area?
• Surface Area Formula of some common solids.
• Examples.
• Important Questions.

Constructions Class 9 Notes: Chapter 12

Class 9 CBSE math notes are provided here to help students overcome the challenges in learning the concepts of constructions. The Constructions Class 9 Notes which contain detailed information can be used as a great reference tool for studying productively as well as completing revisions before the exams. Some of the topics that are covered in the construction chapter are;

• Definition of Construction.
• Carrying out some basic constructions and giving reasons as to why these constructions are valid.
• Constructions of a triangle.
• Practice Questions.