Structure of atom Flashcards
No of e’s prop
intensity of light
KE of e’s increase with
Increase in freq of light
Lymann in
UV
Balmer in
Visible
Paschen, Brackett Pfund in
IR
Max wavelength n1,n2=
n2 = 2 and n1 = 1 in Lymann
Which spectral line has max wavelength?
1st
No of radiations emitted when e’ drops from nth level to ground level
n(n-1)/2
Bohr’s postulates
E’ revolve in circular orbits
Each orbit have fixed energy
E’ can move only in orbits with l = nh/2pi
Bohr merits
Could explain atomic spectra of H
Energy of nth orbit
En = 2.179 Z^2/(10^18 n^2) J/atom
En = -1312 Z^2/n^2 kJ/atom
-13.6 Z^2/n^2 eV/atom
If KE is x, PE is
-2x
Radius of nth orbit
rn = a(o)n^2/Z
Value of a(o)
0.529A*
Velocity of e’ in H
Vn = 2.189x10^6 Z /n
Energy of radiation emitted =
ΔE = 2.189Z^2/10^18(1/n1^2 - 1/n2^2) J
ΔE = 1312Z^2(1/n1^2 - 1/n2^2) kJ
ΔE = 13.6Z^21/n1^2 - 1/n2^2) eV
Bohr’s limitations
Failed to explain atomic spectra of multi e’ species, Zeeman & stark effect, de Broglie nature of matter
As mass increases, which nature increases
particle
Heisenburg uncertainty principl
It is impossible to determine V and position or position & momentum at the same time with accuracy
Δx.Δp = h/4pi
priniciple quantum no N starts from
1 to infinity
K, L, M, N,..
Max no of e’s in nth level
2n^2
