Which one of the following is the strongest base?

An equal volume of a reducing agent is titrated separately with 1M KMnO₄ in acid neutral and alkaline media. The volumes of KMnO₄ required are 20 ml. in acid 33.4 ml. neutral and 100 ml in alkaline media. Find out the oxidation state of manganese in each reduction product. Give the balanced equations for all three half reactions. Find out the volume of 1M K₂Cr₂O₇ consumed; if the same volume of the reducing agent is titrated in acid medium.

The correct set of quantum numbers for the unpaired electron of chlorine atom is

The correct ground state electronic configuration of chromium atom is