Given below are two statements :

Statement I : The pentavalent oxide of group-15 element, E₂O₅, is less acidic than trivalent oxide, E₂O₃, of the same element.

Statement II : The acidic character of trivalent oxide of group 15 elements, E₂O₃, decreases down the group.

In light of the above statements, choose most appropriate answer from the options given below :

Which one of the lanthanoids given below is the most stable in divalent form?

Given below are two statements :

Statement I : [Ni(CN)₄]^2$$-$$ is square planar and diamagnetic complex, with dsp² hybridization for Ni but [Ni(CO)₄] is tetrahedral, paramagnetic and with sp³-hybridication for Ni.

Statement II : [NiCl₄]^2$$-$$ and [Ni(CO)₄] both have same d-electron configuration have same geometry and are paramagnetic.

In light the above statements, choose the correct answer from the options given below :

Which amongst the following is not a pesticide?