A group 15 element forms \(d\pi -d\pi\) bond with transition metals. It also forms hydride, which is a strongest base am…

A group 15 element forms \(d\pi -d\pi\) bond with transition metals. It also forms hydride, which is a strongest base among the hydrides of other group members that form \(d\pi -d\pi\) bond. The atomic number of the element is _______

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