Inspired by Alfred Werner (1866-1919), a KOTA student decided to reconduct a similar experiment on unknown salt samples of `MCl_(3).xNH_(3)`. The student found that some of the chloride ions could be prdipitated as AgCl on adding silver nitrate solution. He found that this salt was of 4 years (based on colour). He labelled these complexes as A (yellow complex) B( purple complex), C (Green complex), D (violet complex).
He found that moles of AgCl precipitated (per mole of salt) in one case was 3, one case it was 2, and in two cases it was one.
He then measured the electrical conductivity of various salt solutions and found that D had the lowest value.
He then measured the boiling point of solutions of A, B, C, D and found that B had the 2nd highest boiling point, Based on the above information, answer the following questions.
If all the complexes taken by the student were cystalline, then, what is the possible molecular formula of the complex having least boiling point?

Options

A. `MCl_(3).6NH_(3)`
B. `MCl_(3).5NH_(3)`
C. `MCl_(3).4NH_(3)`
D. `MCl_(3).2NH_(3)`

Answer

C

Explanation

`[M(NH_(3))_(4)Cl_(2)]Cl` has i=2 while (a) and (b) have i=4 and i=3 respectively. Hence, (c ) has least elevation in B.P.