How much energy is emitted out when a mole of electron falls in 1g atom of H from 2 to 1 orbit?(Rh=109678 cm-1)

Dear student,

Use 1/l=RZ2(1/n1^2-1/n^2)

E=hc/l

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Askiitians Expert

Sagar Singh

B.Tech, IIT Delhi

E = 13.6 (1-1/n²)       

this is the energy librated when 1 electron falls from n=n to n=1

for 1 mol of electrons or  N_a number of electrons energy will be

E_T = 13.6 N_a(1-1/n²)

n = 2      (given)

N_a = 6 * 10²³

E_T = 13.6*(3/4)*6*10²³

E_T = 6.12*10²⁴ ev

1 ev = 1.6*10^-19 J so

E_T = 9.8*10⁵ J or 980  KJ

Approved