<Dd> so that the allowed orbit radius at any n is: <Dl> <Dd> r n = n 2 ħ 2 Z k e e 2 m e (\ displaystyle r_ (n) = (n ^ (2) \ hbar ^ (2) \ over Zk_ (\ mathrm (e)) e ^ (2) m_ (\ mathrm (e)))) </Dd> </Dl> </Dd> <Dl> <Dd> r n = n 2 ħ 2 Z k e e 2 m e (\ displaystyle r_ (n) = (n ^ (2) \ hbar ^ (2) \ over Zk_ (\ mathrm (e)) e ^ (2) m_ (\ mathrm (e)))) </Dd> </Dl> <Dd> r n = n 2 ħ 2 Z k e e 2 m e (\ displaystyle r_ (n) = (n ^ (2) \ hbar ^ (2) \ over Zk_ (\ mathrm (e)) e ^ (2) m_ (\ mathrm (e)))) </Dd> <Dl> <Dd> The smallest possible value of r in the hydrogen atom (Z = 1) is called the Bohr radius and is equal to: <Dl> <Dd> r 1 = ħ 2 k e e 2 m e ≈ 5.29 × 10 − 11 m (\ displaystyle r_ (1) = (\ hbar ^ (2) \ over k_ (\ mathrm (e)) e ^ (2) m_ (\ mathrm (e))) \ approx 5.29 \ times 10 ^ (- 11) \ mathrm (m)) </Dd> </Dl> </Dd> </Dl>

What purpose do valence electrons serve in an atom