To solve the problem, we analyze the fluorination reaction of phosphorus pentachloride (PCl5) in a polar organic solvent.
Fluorination of PCl5:
When PCl5 reacts with fluorine or a fluorinating agent in polar organic solvents, it often forms ionic species due to ligand exchange and formation of complex ions.
Known species formed:
- The cation [PCl4]+ (tetrachlorophosphonium ion)
- The anion [PF6]- (hexafluorophosphate ion)
These ions result from partial substitution of chlorine by fluorine in PCl5 and subsequent complex formation.
Therefore, the species formed are:
\[
[PCl_4]^+ [PF_6]^-
\]
Final Answer:
\[
\boxed{\text{[PCl}_4]^+ \text{[PF}_6]^-\ \text{and not the other species}}
\]
which corresponds to the second option:
[PCl4]+[PCl4F2]- and [PCl4]+[PF6]-
How many of the following molecules / ions have a trigonal planar structure?
\( \text{BO}_3^{3-}, \, \text{NH}_3, \, \text{PCl}_3, \, \text{BCl}_3, \, \text{ClF}_3, \, \text{XeO}_3 \)
Two identical concave mirrors each of focal length $ f $ are facing each other as shown. A glass slab of thickness $ t $ and refractive index $ n_0 $ is placed equidistant from both mirrors on the principal axis. A monochromatic point source $ S $ is placed at the center of the slab. For the image to be formed on $ S $ itself, which of the following distances between the two mirrors is/are correct: