$AlF_3$ is soluble in $HF$ only in the presence of $KF$. This is due to the formation of:

With which of the following will ammonia $NOT$ form a complex compound?

Which of the following coordination compounds acts as a non-electrolyte in solution?

When concentrated $HCl$ is added to an aqueous solution of $CoCl_2$,its colour changes from reddish pink to deep blue. Which complex ion gives blue colour in this reaction?

The most stable ion is

Violet colour of $[Ti(H_2O)_6]Cl_3$ on heating changes to $........$