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Assertion (A): pure water obtained from ...

Assertion (A): pure water obtained from different states of india always contains hydrogen and oxygen in the ration of 1:8 by mass.
Reason (R ): Total mass of reactants and products during chemical change is always the same.

A

If both (A) and (R ) are correct and (R ) is the correct explantion for (A)

B

If both (A) and (R ) are correct but (R ) is not the correct explantion for (A)

C

If (A) is correct but (R ) is incorrect.

D

If (A) and (R ) are incorrect.

Text Solution

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To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states that "pure water obtained from different states of India always contains hydrogen and oxygen in the ratio of 1:8 by mass." - **Understanding the Composition of Water**: Water (H₂O) is composed of two hydrogen atoms and one oxygen atom. The molar mass of hydrogen is approximately 1 g/mol, and the molar mass of oxygen is approximately 16 g/mol. - **Calculating the Mass Ratio**: - Mass of hydrogen in water = 2 × 1 g/mol = 2 g - Mass of oxygen in water = 16 g/mol - Therefore, the mass ratio of hydrogen to oxygen in water = 2 g : 16 g = 1 : 8. **Conclusion for Step 1**: The assertion is correct as pure water does indeed have a mass ratio of hydrogen to oxygen of 1:8. ### Step 2: Analyze the Reason The reason states that "the total mass of reactants and products during a chemical change is always the same." - **Understanding the Law of Conservation of Mass**: This principle states that in a closed system, the mass of the reactants must equal the mass of the products in a chemical reaction. This law is fundamental in chemistry and applies to all chemical reactions. **Conclusion for Step 2**: The reason is also correct as it accurately describes the law of conservation of mass. ### Step 3: Determine the Relationship Between Assertion and Reason Now we need to evaluate whether the reason correctly explains the assertion. - **Assertion vs. Reason**: While both statements are true, the reason does not explain why water has a specific mass ratio of hydrogen to oxygen. The assertion is based on the law of definite composition, which states that a chemical compound always contains the same proportion of elements by mass. **Final Conclusion**: Both the assertion and the reason are correct, but the reason does not provide the correct explanation for the assertion. ### Final Answer - **Assertion (A)**: True - **Reason (R)**: True - **Correct Relationship**: Both assertion and reason are correct, but reason is not the correct explanation of the assertion.
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states that "pure water obtained from different states of India always contains hydrogen and oxygen in the ratio of 1:8 by mass." - **Understanding the Composition of Water**: Water (H₂O) is composed of two hydrogen atoms and one oxygen atom. The molar mass of hydrogen is approximately 1 g/mol, and the molar mass of oxygen is approximately 16 g/mol. - **Calculating the Mass Ratio**: - Mass of hydrogen in water = 2 × 1 g/mol = 2 g ...
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