The weightage of chapters in the board paper of Science for Class 10 may vary depending on the specific education board and curriculum followed. However, I can provide a general overview of the chapters and their weightage based on common patterns observed in different boards.

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Chapters and Weightage in Class 10 Science Board Paper:

1. Chemical Substances - Nature and Behavior (Periodic Classification of Elements) :
- This chapter generally carries a weightage of around 4-5 marks.
- Key topics include the modern periodic table, trends in the properties of elements, and the identification of elements based on their properties.

2. World of Living (Life Processes) :
- This chapter typically carries a weightage of around 6-8 marks.
- Key topics include nutrition, respiration, transportation, excretion, and control and coordination in living organisms.

3. Natural Phenomena (Magnetic Effects of Electric Current) :
- This chapter usually carries a weightage of around 5-6 marks.
- Key topics include magnetic field and field lines, electromagnetic induction, and electric motor and generator.

4. Effects of Current (Electricity) :
- This chapter generally carries a weightage of around 7-8 marks.
- Key topics include electric current, circuits, Ohm's law, resistors, and electric power.

5. Natural Resources (Management of Natural Resources) :
- This chapter typically carries a weightage of around 5-6 marks.
- Key topics include the importance and conservation of natural resources, management of forests and wildlife, and sustainable practices.

6. Our Environment (Control and Coordination) :
- This chapter usually carries a weightage of around 4-5 marks.
- Key topics include the ecosystem, food chains and webs, waste management, and environmental issues.

7. Light - Reflection and Refraction :
- This chapter generally carries a weightage of around 10-12 marks.
- Key topics include reflection, refraction, spherical mirrors, lenses, and human eye.

8. Chemical Reactions (Chemical Reactions and Equations) :
- This chapter typically carries a weightage of around 5-6 marks.
- Key topics include different types of chemical reactions, balancing chemical equations, and the importance of chemical reactions in daily life.

9. Acids, Bases, and Salts :
- This chapter usually carries a weightage of around 7-8 marks.
- Key topics include the properties of acids and bases, pH scale, chemical reactions involving acids and bases, and the importance of salts.

10. Metals and Non-metals :
- This chapter generally carries a weightage of around 6-8 marks.
- Key topics include the properties of metals and non-metals, reactivity series, extraction of metals, and the importance of metals in daily life.

11. Carbon and its Compounds :
- This chapter typically carries a weightage of around 6-8 marks.
- Key topics include bonding in carbon compounds, nomenclature, functional groups, and some important carbon compounds like ethanol and ethanoic acid.

12. Life Processes (Control and Coordination) :
- This chapter usually carries a weightage of

Chemistry :25biology: 23physics : 25 natural resource : 7hope its help you...