Class 10 Science - HARYANA
Chemical Reactions and Equations
The chapter Chemical Reactions and Equations in Class 10 Science for Haryana (BSEH) board introduces students to how chemical changes occur. You will learn to identify chemical reactions through observations like state change, colour change, gas evolution, or temperature change. The chapter teaches how to write word equations and balance skeletal chemical equations using the Law of Conservation of Mass. Furthermore, it covers different types of chemical reactions—combination, decomposition, displacement, double displacement, oxidation, and reduction—along with everyday phenomena like corrosion and rancidity, which are crucial scoring topics for your board examinations.
Start Learning FreeKey Concepts
Chemical Equation
A representation of a chemical reaction using symbols and formulas of the substances involved, where reactants are on the left and products on the right.
Balanced Chemical Equation
An equation in which the number of atoms of each element is equal on both the reactant and product sides, satisfying the Law of Conservation of Mass.
Combination Reaction
A reaction in which two or more reactants combine to form a single product, such as the burning of magnesium or the formation of slaked lime.
Decomposition Reaction
A reaction where a single reactant breaks down into two or more simpler products, usually requiring energy in the form of heat, light, or electricity.
Oxidation and Reduction
Oxidation involves the gain of oxygen or loss of hydrogen, whereas reduction involves the loss of oxygen or gain of hydrogen. Reactions involving both are called redox reactions.
Important Formulas
Board Exam Info
In the Haryana Board (BSEH) Class 10 Science exam, this chapter typically carries around 4 to 6 marks. Questions often include 1-mark objective questions, balancing chemical equations, identifying types of reactions from given examples, and short-answer questions explaining phenomena like rancidity or corrosion.
Frequently Asked Questions
Why must a chemical equation be balanced?
A chemical equation must be balanced to satisfy the Law of Conservation of Mass, which states that matter can neither be created nor destroyed in a chemical reaction.
What is the difference between displacement and double displacement reactions?
In a displacement reaction, a more reactive element displaces a less reactive element from its compound. In a double displacement reaction, two ionic compounds exchange their ions to form two new compounds.
How can we prevent food containing fats and oils from turning rancid?
Rancidity can be prevented by adding antioxidants, storing food in airtight containers, replacing air with nitrogen gas (as done in potato chip packets), and keeping food away from direct sunlight.
Learn Chemical Reactions and Equations with Your AI Tutor
10 different ways to study this chapter. Free for 3 chapters per day.
Lecture
Key Points
Interactive
Quiz
Flashcards