Question

why can we not write the configuration of carbon like copper, in the way copper shifts electron to outer orbital to gain stability

Answer 1

Dear Student,

The electronic configuration of C is 1s^​2 2s² 2p²and electronic configuration of Cu is [Ar] 3d¹⁰ 4s¹. According to the normal trend, electronic configuration of Cu shoukd be 3d⁹ 4s² but it is not. One electron from 4s goes to 3d to attain fully filled d orbital configuration which increases its stability.
In C, the inner orbitals are already fully filled and is stable, therefore electronic configuration of C is not written like Cu.