Q1. If the ionization potential of Li+2 is 122.4 eV. What is the 5th I.P. of carbon.

Q2. What is the wavelength of light required to raise an electron in the O7+ ion from n=1 to shell to n=2 shell.

Q3. What is the radius of Bohrs fifth orbit for B+4.

Q4. If the potential energy of the electron is 10eV what is total energy?

Q5. First and second excitation potentials of hydrogen atom (in eV) would be respectively(A) 10.2, 12.1 (B) 12.1, 10.2 (C) 13.6, 3.4 (D) 3.4, 13.6

Q6. The separation energy of the electron present in the shell n = 3 is 1.51 eV. What is the energy in the firstexicted state ?(A) -1.51eV (B) -3.4eV (C) +1.51 (D) +3.eV

Q7. The energy required for the ionization of excited hydrogen atom would be (in eV)-(A) 13.6 (B) >13.6 (C)

Q1. Supposing the electron of the H-atom is present in the L-shell. If it liberates 10.2eV, what is the energyof the system ?(A) -3.4eV (B) -13.6eV (C) -10.2eV (D) 0eV

Q2. Going from K-shell to N-shell in case of H-atom :(A) K.E. decreases (B) Total energy decreases(C) Potential energy decreases (D) None of the above

Q3. What is the radius ratio for 2nd orbit of Li+2 ion 3rd orbit of Be+3 ion ?(A) 3 : 1 (B) 16 : 27 (C) 4 : 9 (D) 3 : 4

Q4. The ratio of the energy of the electrons in ground state of hydrogen to the electrons in first excited stateof 3Be is :(A) 1:4 (B) 1:8 (C) 1:16 (D) 16:1.

Q5. The total energy of an atomic electron is :(A) Zero (B) Less than zero (C) More than zero(D) Sometimes more and sometimes less than zero

Q6. The expression Ze gives :(A) The charge of particle (B) The charge on an atom(C) The charge on the nucleus of atomic number Z(D) The kinetic energy of an particle

Q7. The energy of the electron at infinite distance from the nucleus in Bohrs model is taken as :(A) Zero (B) Positive (C) Negative (D) Any value

Q8. As an electron is brought from an infinite distance close to the nucleus of the atom, the energy of theelectron-nucleus system :(A) Increases to a greater positive value (B) Decreases to a smaller positive value(C) Decreases to a smaller negative value (D) Increases to a smaller negative value

Q9. The energy of an electron in the first Bohrs orbit of H atom is -13.6eV. The possible energy value (s) ofthe excited state (s) for electron in Bohrs orbits of hydrogen is (are) :(A) -3.4eV (B) -4.2eV (C) -6.8eV (D) +6.8eV

Q10. Which electron transition in a hydrogen atom requires the largest amount of energy :(A) From 1n to 2n (B) From 2n to 3n(C) From n to 1n (D) From 3n to 5n

Q11. Bohrs model of atom explains :(A) Zeeman effect (B) Heisenbergs principle (C) Strak effect (D) None of these

Q12. The ionzation potential of hydrogen atom is 13.6 eV. The energy required to remove an electron from then = 2 state of hydrogen atom is :(A) 27.2 eV (B) 13.6 eV (C) 6.8eV (D) 3.4 eV

Q13. The total energy of the electron in the hydrogen atom in the ground state is -13.6 eV. What is thestopping potential :(A) 13.6 volts (B) Zero (C) -13.6 volts (D) 6.8 volts

Q14. In an atom two electrons move around the nucleus in circular orbits of radii R & 4R. The ratio of the timetaken by them to complete one revolution is :(A) 1 : 4 (B) 4 : 1 (C) 1 : 8 (D) 8 : 7

Q15. Which of the following electronic transitions in a hydrogen atom will require the largest amount of energy(A) from n= 1 to n=2 (B) from n = 2 to n = 3(C) from n = to n = 1 (D) from n = 3 to n = 5

DPP.6

Q1. In Bohrs model of atom when an electron jumps from n =1 to n=3, how much energy will be absorbed(A) ergs101015.2 (B) 0.1911 x 1010ergs (C) 2.389 x 1010ergs (D) 0.239 x 1010ergs

Q2. If energy of the electron in hydrogen atom in some excited state is -3.4eV, then what will be its angularmomentum(A) 1230108.1 skgm (B) 1234101.2 skgm(C) 1237102.9 skgm (D) 1232102.1 skgm

Q3. Potential energy of an electron in the atom is(A) rZe /2 (B) rZe /2 (C) 22 / rZe (D) 22 / rZe

Q4. Electrostatic force of attraction between electron and the nucleus in the hydrogen atom is

(A) re2

(B) 22

re

(C) 22

2re

(D) r

Ze2

Q5. Which one of the following is incorrect for the Bohr model of hydrogen atom

(A) r

mvr

Ze 22

2

(B) angular momentum is quantized(C) mass of proton is ignored (D) none of the above

Q6. In which orbit of the Bohr model of the hydrogen atom is the speed of electron maximum(A) 2n (B) n = 1 (C) 3n (D) 4n

Q7. The mass of the proton is 1840 times that of electron. If a proton is accelerated through a potentialdifference of V volts, the kinetic energy of the proton would be(A) 1 e V (B) 1keV (C) 1840 eV (D) 1849 keV

Q8. With increasing principle quantum number, the energy difference between adjacent energy levels in H atom(A) increases (B) decreases(C) decreases for low value of Z and increases for high value of Z (D) remains constant

Q9. Energy levels A, B, C of a certain atom corresponds to increasing values of energy, ..,. CBA EEEei If

321, and are the wavelength of radiations corresponding to the transitions C to B, B to A and C to AArespectively, which of the following statement is correct :

(A) 3 = 21 (B) 3 = 21

21

(C) 321 = 0 (D)

23 = 22

21

Q10. The energy of an e- in the first Bohr orbit is -13.6 eV in hydrogen atom which one of following is/are possible excited states for electrons in Bohr orbits of hydrogen(A) -3.4 eV (B) -6.8 eV (C) -1.7 eV (D) +13.6 eV

Q11. Assuming that it were possible for such an atom to exist, calculate the energy of a position (a positiveelectron) in the first Bohr orbit of a hydrogen atom(A) -13.6 eV (B) +13.6 eV (C) -3.4 eV (D) +3.4 eV

DPP.7