Exercise

Pyrolusite is

Which of the following is not an example of roasting?

The electronic configuration of chalcogens is :

At which oxidation state iron catalyses the reaction between iodide and persulphate ions and acts as a catalyst?

Which of the following alcohols is prepared by acid catalysed hydration of alkenes?

Dipole moments of aldehydes and ketones are higher than the alcohols. Why?

Name the product formed by the electrolytic reduction of nitro methane.

A dilute solution of $\mathrm{HCl}$ contains $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]=1\times {10}^{-5}$, calculate the $\left[{\mathrm{OH}}^{-}\right]$ of this solution.