On adding excess of ammonium hydroxide to a copper sulphate solution:

$50 \, mL$ of $0.2 \, M$ solution of a compound with empirical formula $CoCl_3 \cdot 4NH_3$ on treatment with excess of $AgNO_{3(aq)}$ yields $1.435 \, g$ of $AgCl$. Ammonia is not removed by treatment with concentrated $H_2SO_4$. The formula of the compound is:

Silver chloride dissolves in excess of $NH_4OH$. The cation present in this solution is

Which of the following is a low-spin complex?

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

The colour of $KMnO_4$ is due to