JEE Main 2025 — D And F Block Elements Question with Solution
From: JEE Main 2025 (Online) 29th January Morning Shift
Question
The molar mass of the water insoluble product formed from the fusion of chromite ore (FeCr₂O₄) with Na₂CO₃ in presence of O₂ is ___________ g mol⁻¹.
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Show full solutionCorrect answer: 159.687
Step-by-step explanation
The chemical reaction can be written as

The insoluble product is .
Molar mass of
Fe (Atomic mass) 55.845 amu
Molar mass = 55.845 g mol
O (Atomic mass) 15.999 amu
Molar mass = 15.999 g mol
Molar mass of = 55.845 g mol + 15.999 g mol
g mol
g mol g mol
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