The aqueous solution of disodium hydrogen phosphate $(Na_2HPO_4)$ is:

Which of the following aqueous solutions of salts will have the highest $pH$ value?

On combining which of the following anions with $NH_4^{\oplus}$ will the $pH$ of the resulting salt solution be independent of the concentration?

What is the correct relationship between the $pH$s of isomolar solutions of sodium oxide $(pH_1)$,sodium sulphide $(pH_2)$,sodium selenide $(pH_3)$ and sodium telluride $(pH_4)$?

Which of the following cannot be hydrolysed?

The aqueous solution of $CuSO_4$ is