When potassium ferrocyanide crystals are heated with concentrated sulphuric acid,the gas evolved is

In the complex ion $[Co(CN)_6]^{3-}$,the $Co^{3+}$ ion absorbs radiation of the violet color from the visible spectrum. What will be the color of its aqueous solution?

In any ferric salt,on adding potassium ferrocyanide,a Prussian blue colour is obtained,which is:

Sodium thiosulphate $(Na_2S_2O_3 \cdot 5H_2O)$ is used in photography to

When $CuSO_4$ solution is added to $K_4[Fe(CN)_6]$,the formula of the product formed is

To inhibit the growth of tumours,identify the compounds used from the following:
$(A)$ $EDTA$
$(B)$ Coordination Compounds of $Pt$
$(C)$ $D$-Penicillamine
$(D)$ $Cis-Platin$
Choose the correct answer from the option given below: