JEE Mains · Chemistry · STD 11 - 1. Some basic concept of chemistry
The mass of iron converted into \(Fe_3O_4\) by the action of \(18\) g of steam is :
(Given : Molar mass of H, O and Fe are \(1\), \(16\) and \(56\) g mol\(^{-1}\) respectively)
Assume iron is present in excess :
- A \(2.1\) g
- B \(4.2\) g
- C \(21\) g
- D \(42\) g
Answer & Solution
Correct Answer
(D) \(42\) g
Step-by-step Solution
Detailed explanation
The balanced chemical equation for the reaction of iron with steam is: \(3Fe + 4H_2O \rightarrow Fe_3O_4 + 4H_2\) Molar mass of \(H_2O = 2 \times 1 + 16 = 18 \text{ g mol}^{-1}\) Number of moles of steam (\(H_2O\)) given = \(\dfrac{18}{18} = 1 \text{ mol}\) From the balanced…
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