Question

explain qualitative how quantum mechanical principles can be used to explain the stability of atom

Answer 1

This framework was unable to explain the stability of atoms. Instead, electrons remain in an uncertain, non-deterministic, smeared, probabilistic wave–particle orbital about the nucleus ...The laws of quantum mechanics. Within a few short years scientists developed a consistent theory of the atom that explained its fundamental structure and its interactions. ... By 1926 physicists had developed the laws of quantum mechanics, also called wave mechanics, to explain atomic and subatomic phenomena.

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