When balancing a chemical equation, we keep in mind the Law of Conservation of Mass.
Law of Conservation of Mass:
This law states that mass is neither created nor destroyed in a chemical reaction. Therefore, the total mass of the reactants must equal the total mass of the products.
- Reactants and Products: In a balanced chemical equation, the number of atoms of each element must be the same on both sides of the equation. This ensures that the mass of the reactants equals the mass of the products, in accordance with the law.
For example, in the reaction:
2H2 + O2 → 2H2O
- There are 4 hydrogen atoms and 2 oxygen atoms on both sides of the equation, satisfying the Law of Conservation of Mass.
Other Related Questions For Practicing Before the Exam
- MCQ Test for Chemical Reactions and Equations Class 10
- Support MCQs Answer: Chemical Reactions and Equations Class 10
- Give an example of a double displacement reaction
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- Give reasons: Silver chloride is stored in dark-colored bottles.
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- Identify the chemical change: Melting of ice or conversion of milk into curd.
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- Why do we store silver chloride in dark coloured bottles in labs?
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- Compound ‘X’ decomposes to form compound ‘Y’ and CO₂ gas. Compound Y is used in the manufacturing of cement.
- A metal salt MX, when exposed to light, splits up to form metal M and gas X₂. Metal M is used to make ornaments whereas gas X₂ is used in making bleaching powder. The salt MX is used in black & white photography.
- A metal strip X is dipped in a blue-colored salt solution YSO₄. After some time, a layer of metal ‘Y’ is formed on metal strip X. Metal X is used in galvanization whereas metal Y is used for making electric wires.
- When potassium iodide solution is added to a solution of lead nitrate in a test tube, a precipitate is formed. (CBSE-2015 Comptt)
- Decomposition reactions require energy either in the form of heat or light a electricity for breaking down of reactions. Write one equation for each type of decomposition reaction where heat, light or electricity is used as form of energy.
- 2 gm of silver chloride is taken in china dish, and china dish is placed in sunlight for sometime. What will be your observation. Write the balanced chemical equation for above reaction and identify the type of reaction.
- Identify the type of reactions taking place in each of the following cases and write the balanced chemical equation for the reactions. (a) Zn reacts with silver nitrate to produce zinc nitrate and silver:
- LONG ANSWER TYPE OF QUESTIONS (5 MARKS) Class 10 Supports Answers