JEE Main 2020 — Coordination Compounds Question with Solution
From: JEE Main 2020 (Online) 2nd September Morning Slot
Question
The oxidation states of iron atoms in
compounds (A), (B) and (C), respectively, are x,
y and z. The sum of x, y and z is ________.
Na4[Fe(CN)5(NOS)]
(A)
Na4[FeO4]
(B)
[Fe2(CO)9]
(C)
Na4[Fe(CN)5(NOS)]
(A)
Na4[FeO4]
(B)
[Fe2(CO)9]
(C)
Enter your answer
Show full solutionCorrect answer: 6
Correct answer
6
Step-by-step explanation
Na4[Fe(CN)5(NOS)]
Let the O.S. of Fe be x
OS of CN = –1
OS of NOS = –1
(+1)4 + x + (–1)5 + (–1)1 = 0
x = +2
Na4[FeO4]
Let O.S. of Fe be y
(+1)4 + y + (–2)4 = 0
y = +4
[Fe2(CO)9]
Let O.S. of Fe be z
2z + 0 × 9 = 0
z = 0
so (x + y + z) = +2 + 4 + 0 = 6
Let the O.S. of Fe be x
OS of CN = –1
OS of NOS = –1
(+1)4 + x + (–1)5 + (–1)1 = 0
x = +2
Na4[FeO4]
Let O.S. of Fe be y
(+1)4 + y + (–2)4 = 0
y = +4
[Fe2(CO)9]
Let O.S. of Fe be z
2z + 0 × 9 = 0
z = 0
so (x + y + z) = +2 + 4 + 0 = 6
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