Which of the following complex species is not expected to exhibit optical isomerism?

Four successive members of the first row transition elements are listed below with atomic numbers. Which one of them is expected to have the highest $$E_{{M^{3 + }}/{M^{2 + }}}^0$$ value?

Which of the following arrangements does not represent the correct order of the property stated against it?

The rate of a reaction doubles when its temperature changes from 300K to 310K. Activation energy of such a reaction will be:(R = 8.314 JK^–1 mol^–1 and log 2 = 0.301)