`A,B` and `C` are three complexes of chromium(III) with the empirical formula `H_(12)O_(6)C_(13)Cr` All the three complexes not react with concentrated `H_(2)SO_(4)` whereas complexes `B` and `C` lose `6.75%` and `13.5%` of their original mass respectively, on treatment on treatment with conectrated `H_(2)SO_(4)` Identify `A,B` and `C` .

Options

A. `[Cr(H_(2)O)_(4)Cl_(2)]Cl.2H_(2)O`
B. `[Cr(H_(2)O)_(3)Cl_(3)].3H_(2)O`
C. `[Cr(H_(2)O)_(5)Cl]Cl_(2).H_(2)O`
D. `[Cr(H_(2)O)_(6)]Cl_(3)`

Answer

C

Explanation

`B=[Cr(H_(2)O)_(5)Cl]Cl_(2).H_(2)O overset(H_(2)SO_(4))rarr` one mole of `H_(2)O` is removed.
Molecular weight of the complex = 266.5
`%" loss "=(18)/(266.5)xx100=6.75%`