Select the correct $M-C$ bond order.

Which of the following compounds give at least $1$ mole of $AgCl$ precipitate with $100$ mL of a $10$ $M$ solution of $AgNO_3$?

In the change $[Cu(H_2O)_6]^{2+} \xrightarrow{HCl} [CuCl(H_2O)_5]^+$,the colour changes from

What is the final product formed when copper sulphate solution reacts with excess $KCN$?

Ammonia forms the complex ion $[Cu(NH_3)_4]^{2+}$ with copper ions in alkaline solutions but not in acidic solution. What is the reason for it?

Choose the correct statements from the following:
$A$. Ethane$-1, 2-$diamine is a chelating ligand.
$B$. Metallic aluminium is produced by electrolysis of aluminium oxide in the presence of cryolite.
$C$. Cyanide ion is used as a ligand for the leaching of silver.
$D$. Phosphine acts as a ligand in Wilkinson's catalyst.
$E$. The stability constants of $Ca^{2+}$ and $Mg^{2+}$ are similar with $EDTA$ complexes.
Choose the correct answer from the options given below: