Structure of Atom
SHORT NOTES
2
Charge to Mass Ratio of Fundamental Particles ∆E = E E = 13.6 1 1 eV = IE 1 1
– – –
Electron
n2
n
Z1 n2 n22 ato n21 n22
Proton 1 m
(mP)/anode Neutron (mn)
(me)
rays where, IE = ionization energy of single electron
/cathode
mass = 1.67 × 10– mass=1.67×10–27kg mass=9.1×10–31 kg species.
Ionization energy = E∞ – EG.S. = 0 – EG.S.
27kg
mass = 1.67 × 10–24 mass = 1.67 × 10–24 mass = 9.1 × 10–28
g g g
EG.S.= Energy of electron in ground state
mass = 1.00727 mass = 1.00867 mass = 0.000549 2
amu amu amu Z
e/m of electron E = –2.18 × 10–11
e/m value is n erg per atom
dependent on the 2
is found to be Z
nature of gas = –2.18 × 10–18
independent of n J per atom
taken in discharge nature of gas & 2
tube. Z
electrode = –13.6
Electromagnetic Spectrum n eV/atom
RW → MW → IR → Visible → UV → X-rays → CR 1 eV = 3.8 3 × 10–23 kcal
(Radiowaves→ Microwaves → Infrared rays→Visible 1 eV = 1.602 × 10–12erg
rays → Ultraviolet rays → X-rays → Cosmic rays) 1 eV = 1.602 × 10–19 J
Wavelength decreases → Z
2
Frequency increases → E=–313.6
n kcal/mole(1cal=4.18J)
c 1 v 2 2
c = vl λ= ν= = Z
v λ c V = kZeπ V∝
1 h nh n
T= E =c = hv, h = 6.626 × 10–34 Js nh2 n
2
v λ r= r∝
12400 4 π2 mk 2 Z
E(ev) = Ze
λ (A) −π 2mZ e k 2 Z2
E= E∝
nhc 2 n 2 n2
Total amount of energy h
E= nv h
=λ
transmitted Hydrogen Spectrum
Bohr’s Atomic Model
Rydberg’s Equation:
Theory based on quantum theory of radiation and the 1 1
1
classical
awsopyscs = v= R H 2 – 2 ×Z2
λ n1 n2
n2
Radius: r =0.52 × Å RH≅ 109700 cm–1 = Rydberg constant
9 Z
For first line of a series, n2 = n1 + 1
6Z
Velocity: v =2.188
–1
10× m Limiting spectral line (series limit) means n2 = ∞
n
Ha line means n2 = n + 1; also known as line of longest
Energy (KE + PE) = Total energy = – Z2eV/atom shortest v, least E
13.6× n
TE =– KZ
2
PE –
2
KE = KZ
2 Similarly, Hb line means n2 = n1 + 2
e , = KZe , e
When electron de-excite from higher energy level (n) to
2r r 2r
PE = –2KE, KE = –TE, PE = 2TE ground state in atomic sample, then number of
2 spectral lines
Rlti=v ∝ Z
evouonspersec 2 rπ 3 observed in the spectrum = n(n –1)
n When electrons de-excite from higher energy level (n2
3
Timeforonerevolution=2 ∝ n lower energy level (n1) in atomic sample, then number
rπ v Z2 tllibditht= (n – n )(n – n 1 + 1)
Energydiferencebetweenn1 and n2 energy level is given specraneoservenespecrum 2
by:
1
SHORT NOTES
2
Charge to Mass Ratio of Fundamental Particles ∆E = E E = 13.6 1 1 eV = IE 1 1
– – –
Electron
n2
n
Z1 n2 n22 ato n21 n22
Proton 1 m
(mP)/anode Neutron (mn)
(me)
rays where, IE = ionization energy of single electron
/cathode
mass = 1.67 × 10– mass=1.67×10–27kg mass=9.1×10–31 kg species.
Ionization energy = E∞ – EG.S. = 0 – EG.S.
27kg
mass = 1.67 × 10–24 mass = 1.67 × 10–24 mass = 9.1 × 10–28
g g g
EG.S.= Energy of electron in ground state
mass = 1.00727 mass = 1.00867 mass = 0.000549 2
amu amu amu Z
e/m of electron E = –2.18 × 10–11
e/m value is n erg per atom
dependent on the 2
is found to be Z
nature of gas = –2.18 × 10–18
independent of n J per atom
taken in discharge nature of gas & 2
tube. Z
electrode = –13.6
Electromagnetic Spectrum n eV/atom
RW → MW → IR → Visible → UV → X-rays → CR 1 eV = 3.8 3 × 10–23 kcal
(Radiowaves→ Microwaves → Infrared rays→Visible 1 eV = 1.602 × 10–12erg
rays → Ultraviolet rays → X-rays → Cosmic rays) 1 eV = 1.602 × 10–19 J
Wavelength decreases → Z
2
Frequency increases → E=–313.6
n kcal/mole(1cal=4.18J)
c 1 v 2 2
c = vl λ= ν= = Z
v λ c V = kZeπ V∝
1 h nh n
T= E =c = hv, h = 6.626 × 10–34 Js nh2 n
2
v λ r= r∝
12400 4 π2 mk 2 Z
E(ev) = Ze
λ (A) −π 2mZ e k 2 Z2
E= E∝
nhc 2 n 2 n2
Total amount of energy h
E= nv h
=λ
transmitted Hydrogen Spectrum
Bohr’s Atomic Model
Rydberg’s Equation:
Theory based on quantum theory of radiation and the 1 1
1
classical
awsopyscs = v= R H 2 – 2 ×Z2
λ n1 n2
n2
Radius: r =0.52 × Å RH≅ 109700 cm–1 = Rydberg constant
9 Z
For first line of a series, n2 = n1 + 1
6Z
Velocity: v =2.188
–1
10× m Limiting spectral line (series limit) means n2 = ∞
n
Ha line means n2 = n + 1; also known as line of longest
Energy (KE + PE) = Total energy = – Z2eV/atom shortest v, least E
13.6× n
TE =– KZ
2
PE –
2
KE = KZ
2 Similarly, Hb line means n2 = n1 + 2
e , = KZe , e
When electron de-excite from higher energy level (n) to
2r r 2r
PE = –2KE, KE = –TE, PE = 2TE ground state in atomic sample, then number of
2 spectral lines
Rlti=v ∝ Z
evouonspersec 2 rπ 3 observed in the spectrum = n(n –1)
n When electrons de-excite from higher energy level (n2
3
Timeforonerevolution=2 ∝ n lower energy level (n1) in atomic sample, then number
rπ v Z2 tllibditht= (n – n )(n – n 1 + 1)
Energydiferencebetweenn1 and n2 energy level is given specraneoservenespecrum 2
by:
1
