Same chapter3 marksDifficulty: Medium
Calculate the number of moles in 5.6 g of nitrogen gas. (N = 14)
Some Basic Concepts of Chemistry
3 marksDifficulty: Medium
State the law of conservation of mass and the law of constant proportions.
Original Khojo Papers practice question — not from a past board paper.
Answer
The law of conservation of mass states that matter is neither created nor destroyed in a chemical reaction, so the total mass of the products equals that of the reactants. The law of constant proportions states that a given compound always contains the same elements combined in the same proportion by mass, however it is prepared.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The second law is why a chemical formula has a fixed meaning.
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