Balance the chemical equation: a Fe + b H₂O → c Fe₃O₄ + d H₂. The values of a, b, c, and d are: MCQ with Answer and Explanation

Balance the chemical equation: a Fe + b H₂O → c Fe₃O₄ + d H₂. The values of a, b, c, and d are:
A. 4, 3, 1, 4
B. 1, 3, 4, 3
C. 3, 4, 1, 4
D. 3, 1, 4, 4
Answer: Option C
Solution (By JKSSB Mock Tests)
To balance the equation: Fe atoms: 3 on right, so a=3. O atoms: 4 on right, so b=4. H atoms: 4*2=8 on left, so d=4. The balanced equation is 3Fe + 4H₂O → Fe₃O₄ + 4H₂. Thus, a=3, b=4, c=1, d=4. This ensures the law of conservation of mass is obeyed.

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