Can you help me with all the formulas we are gonna use in Chapter Atomic Structure of class XI Chemistry?
From CBSE level question to the JEE level questions?
ALL FORMULAE!
Can you help me with all the formulas we are gonna use in Chapter Atomic Structure of class XI Chemistry?
From CBSE level question to the JEE level questions?
ALL FORMULAE!
1. Velocity of electron in nth orbit = vn = 2.165 x 106 Z/n m/s
2. Radius of nth orbit = rn = 0.53 x 10–10 n2/Z m
3. Binding energy of an electron in nth state = En = –13.6 Z2/n2 eV/atom
En = –2.17 × 10–16 Zn2/n2 J/atom = –13.6 Zn2/n2 eV/atom
4. Kinetic energy = KE = 1/2 mv2n = KZe2 / rn
5. Potential energy = PE = –kZe2 / 2rn
6. Total energy of an electron = –En = –kZe2 / 2rn
PE = 2TE ; PE = –2KE ; TE = –KE
7. Binding energy of an electron in nth state
En = –13.6 / n2 Z2 eV
8. Ionisation Energy = – B.E.
I.E. = + 13.6 / n2 Z2 eV
9. Ionisation Potential
Ionisation potential = I.E. / e = 13.6/n2 Z2 V
10. Excitation Energy
The energy taken up by an electron to move from lower energy level to higher energy level. Generally it defined from ground state.
• Ist excitation energy = transition from n1 = 1 to n2 = 2
• IInd excitation energy = transition from n1 = 1 to n2 = 3
• IIIrd excitation energy = transition from n1 = 1 to n2 = 4 and so on …
• The energy level n = 2 is also called as Ist excited state.
• The energy level n = 3 is also called as IInd excited state. & so on …
In general, excitation energy (ΔE) when an electron is excited from a lower state n1 to any higher state n2 is given as:
ΔE = 13.6 Z2 (1/n12 – 1/n22) eV
11. Energy released when an electron jumps from a higher energy level (n2) to a lower energy level (n1) is given as:
ΔE = 13.6 Z2 (1/n12 – 1/n22) eV
If v be the frequency of photon emitted and λ be the wavelength, then:
ΔE =hv = h c/λ
The wavelength (λ) of the light emitted an also be determined by using:
1/λ = v = R Z2 (1/n12 – 1/n22)
R = 1.096 x 107 /m
Important: Also remember the value of 1/R = 911.5 Å for calculation of λ to be used in objectives only).
12. The number of spectral lines when an electron falls from n2 to n1 = 1 (i.e. to the ground state) is given by:
No. of lines = n2(n2–1) / 2
If the electron falls from n2 to n1, then the number of spectral lines is given by:
No. of lines = (n2 – n1 + 1) (n2–n1) / 2
1. Velocity of electron in nth orbit = vn = 2.165 x 106 Z/n m/s
2. Radius of nth orbit = rn = 0.53 x 10–10 n2/Z m
3. Binding energy of an electron in nth state = En = –13.6 Z2/n2 eV/atom
En = –2.17 × 10–16 Zn2/n2 J/atom = –13.6 Zn2/n2 eV/atom
4. Kinetic energy = KE = 1/2 mv2n = KZe2 / rn
5. Potential energy = PE = –kZe2 / 2rn
6. Total energy of an electron = –En = –kZe2 / 2rn
PE = 2TE ; PE = –2KE ; TE = –KE
7. Binding energy of an electron in nth state
En = –13.6 / n2 Z2 eV
8. Ionisation Energy = – B.E.
I.E. = + 13.6 / n2 Z2 eV
9. Ionisation Potential
Ionisation potential = I.E. / e = 13.6/n2 Z2 V
10. Excitation Energy
The energy taken up by an electron to move from lower energy level to higher energy level. Generally it defined from ground state.
• Ist excitation energy = transition from n1 = 1 to n2 = 2
• IInd excitation energy = transition from n1 = 1 to n2 = 3
• IIIrd excitation energy = transition from n1 = 1 to n2 = 4 and so on …
• The energy level n = 2 is also called as Ist excited state.
• The energy level n = 3 is also called as IInd excited state. & so on …
In general, excitation energy (ΔE) when an electron is excited from a lower state n1 to any higher state n2 is given as:
ΔE = 13.6 Z2 (1/n12 – 1/n22) eV
11. Energy released when an electron jumps from a higher energy level (n2) to a lower energy level (n1) is given as:
ΔE = 13.6 Z2 (1/n12 – 1/n22) eV
If v be the frequency of photon emitted and λ be the wavelength, then:
ΔE =hv = h c/λ
The wavelength (λ) of the light emitted an also be determined by using:
1/λ = v = R Z2 (1/n12 – 1/n22)
R = 1.096 x 107 /m
Important: Also remember the value of 1/R = 911.5 Å for calculation of λ to be used in objectives only).
12. The number of spectral lines when an electron falls from n2 to n1 = 1 (i.e. to the ground state) is given by:
No. of lines = n2(n2–1) / 2
If the electron falls from n2 to n1, then the number of spectral lines is given by:
No. of lines = (n2 – n1 + 1) (n2–n1) / 2
