Every great scientist was once just a science student. Great minds attract innovative studies. Science is one of those fields that students wish to study to know more about space, organisms, and much more. Not every science student wants to become a scientist but this subject is the basis for every field of work that one wishes to pursue in the future. There are so many people that you meet throughout your life but you only stay connected to the ones who are important to you while keeping a bare minimum contact with the others. In the same way, when you study for your class 10 science exam, you need to shed some light on all topics but focus on the important ones more. You can spend hours going over the theories, definitions, and diagrams, but you would possibly still find yourself feeling that you simply haven’t done enough. Hence, if you're studying science, then you ought to never skip the questions. Here is a list of chapters that you need to focus on while preparing from ncert science class 10 : 

1. Chemical Reactions and Equations

Every day in our life, we see different kinds of physical and chemical changes. A physical change is a change that can be reversed like the burning of a candle or the water freezing. A chemical change is a change that cannot be reversed, varying from the digestion of food to rusting of iron. All chemical changes are associated with chemical reactions and they are represented by equations. In this segment, you will study the different kinds of chemical changes represented by chemical reactions and the chemical equations.

1. Acids, Bases, and Salts

This chapter will help students study salts, their nature, pH, the chemicals that are derived from salt, and therefore the nature and characteristics of salt crystals. The chapter is divided into 2 parts. One part of the chapter includes various interactive activities and interesting topics such as similarities between acid and base and acid or base in a water solution to make the training process straightforward and straightforward to know. Another part includes topics such as How do Acids and Bases react with each other or metals, Reaction of acid with Hydrogen carbonates and Metallic oxides, and Reaction of bases with oxides to make students understand the basic concepts. 

1. Metals and Non-metals

It will help students understand the metal's occurrence. The extraction of ores, the extraction of metals, the extraction of minerals within the activity series, and therefore the extraction of metals to the highest of the activity series can also explain how metals are often extracted and help produce ores.

1. Carbon and Its Compounds

You will learn about how Carbon is a unique element and it occurs in several forms. You will see some sorts of Carbon that are considered pure than some forms which aren't pure like coal. It is a mixture of both Carbon and hydrogen. It is soft to the touch and is dark grey or black in appearance. One of the vital compounds of Carbon is charcoal. Charcoal develops once you heat carbon within the absence of air. It occurs in plenty of allotropic forms. The density of the varied sorts of Carbon depends upon the origin of those components.

1. Periodic Classification of Elements

This chapter completely focuses on various types and concepts of different periodic tables like

• Achievements of Mendeleev's Periodic Table
• Limitations of Mendeleev's Periodic Table
• Modern Periodic Table
• Position of Elements within the Modern table
• Trends in the Modern Periodic Table

6. Life Processes

Animals and mammals all have a well-defined systema respiratorium for performing respiration tasks. The concept of respiration will be introduced - which is basically how all living beings can intake oxygen and exhale carbon dioxide. As a definition, respiration is said to be the exchange of gases as well as the burning of food. It tells students about metabolism, which is a chemical process that occurs in a human body responsible for controlling the human state of the cells in an organism. 

7. Control and Coordination

It sheds light on topics like human brain anatomy, nervous tissue action, endocrine system.

8. Heredity and Evolution

It is an extremely crucial and scoring chapter in the Science syllabus and students can get a lot of questions regarding this topic. The chapter is divided into several topics that include :

Evolution by Stages

These organs or changes have not occurred overnight. They have appeared eventually after browsing various generations and decades. The Evolution of is traced through excavations, fossils, time dating, and so on.

Fossils

Fossils are remains of living organisms of the past. These remains decompose over time and solidify. They are formed in layers.

Acquired and Inherited Traits

Inherited traits are those which are caused as a result of a change within the DNA of germs cells whereas acquired traits are caused due to a change in non-reproductive tissues, and not passed through DNA. This part of the chapter talks about the difference between them.

Sex Determination

The mechanism behind an offspring's sex determination isn't equivalent for all organisms. In some animals, it's determined by external factors like temperature while in some organisms, it's determined through genetic factors.

Mendel’s Law of Inheritance of Traits

Gregor John Mendel’s experiments and theories are to be mentioned in this part He is referred to as the ‘Father of Genetics’

9. Human Eye and Colourful World

It emphasizes the understanding of the human eye working along with different functions performed by the human eye. It is a very scoring chapter so students should focus on it.

There are a few more chapters other than this but you should pay more attention to the above-mentioned ones and keep revising the others. Happy learning and best of luck with your board exams!