Con que elementos de la tabla periódica, calcio forma un radio de 1: 1?

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

Rate law for this reaction israte of the reaction = k[a]²[b].second order in a  means concentration of a in power of two, and  first order in b means concentration of b in power of one.

Ijust took the quiz. their is no coefficient needed. : )

If this is a true or galse then its true but if not then what is the question?