The $$IUPAC$$ name of the compound is

Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them?

Among the following compounds which can be dehydrated very easily is

In a first order reaction, the concentration of the reactant decreases from 0.8 M to 0.4 M in 15 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M is