NTA Abhyas JEE Main2020Chemistryd and f Block ElementsPractice
Which of the following arrangement does not represent the correct order of the property stated against it?
Options
- AV 2 + < C r 2 + < M n 2 + < F e 2 + : paramagnetic behaviour
- BS c < T i < C r < M n : number of oxidation states
- CC o 3 + < F e 3 + < C r 3 + < S c 3 + : stability in aqueous solution
- DN i 2 + < C o 2 + < F e 2 + < M n 2 + : ionic size
Correct answer
A. V 2 + < C r 2 + < M n 2 + < F e 2 + : paramagnetic behaviour
Step-by-step solution
A. V 2 + has 3 unpaired electrons C r 2 + has 4 unpaired electrons M n 2 + has 5 unpaired electrons F e 2 + has 4 unpaired electrons Hence the order of paramagentic behaviour should be V 2 + < C r 2 + = F e 2 + < M n 2 + B. Ionic size decreases from left to right in same period. C. As per data, we have Co 3 + | Co 2 + = 1.97 ;   Fe 3 + | Fe 2 + = 0.77 ;   Cr 3 + | Cr 2 + = − 0.41 S c 3 + is highly stable, because it does not show +2. D. The oxidation state increases as we g