GUIDED REVISION ENTHUSIAST & LEADER

Target : JEE(Main + Advanced) - 2019 COURSE

PHYSICAL CHEMISTRY
GUIDED REVISION PLAN-SCORE ADVANCED
Topic : ATOMIC STRUCTURE (Question Bank # 15)
SECTION–I : (i) Only One option correct Type
This section contains 10 multiple choice questions. Each question has four choices (A), (B), (C) and
(D) out of which ONLY ONE is correct. 3(–1)
1. In a hydrogen like species , an electron jumps from an orbital having two radial and two angular
nodes to the orbital having same sign of wave function in all direction, at any distance. If the
energy of emitted photon is 326.4 eV, the atom or ion is
(A) H (B) Li2+ (C) He+ (D) B4+
2. O2 undergoes photochemical dissociation into one normal oxygen atom and one oxygen atom,
1.2 eV more energetic than normal. The dissociation of O2 into two normal atoms of oxygen requires
482.5 kJ/mol. The maximum wavelength effective for photochemical dissociation of O2 is
(1 eV = 96.5 kJ/mol)
(A) 248 nm (B) 1033.3 nm (C) 1236.2 nm (D) 200 nm
3. In a measurement of the quantum efficiency of photosynthesis in green plants, it was found that 9
quanta of red light at 6900 Å were needed to evolve 1 molecule of O2. The average energy storage in
the photosynthesis process is 111.6 kcal/mol of O2 evolved. What is the energy conversion efficiency
in this experiment?
h.c
(  1.24  10 7 nm.eV, 1eV = 23kcal/mol)
e
(A) 70% (B) 50% (C) 40% (D) 30%
4. An electron revolving around H-nucleus in ground state absorbs 10.2 eV energy. Its angular momentum
increases by

h h 2h h
(A) (B) (C) (D)
2   4

5. The given diagram shows points P1, P2 P3 & P4 in 1s orbital.

The correct order of radial probability density at these point are

(A) P1 = P2 = P4 > P3 (B) P1 = P3 < P2 = P4 (C) P1 = P3 > P2 = P4 (D)P1 = P2 = P4 < P3
6. Which electronic level would allow the hydrogen atom to absorb a photon but not to emit a photon
(A) 3s (B) 2p (C) 2s (D) 1s

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 GUIDED REVISION ENTHUSIAST & LEADER
Target : JEE(Main + Advanced) - 2019 COURSE

7. Assuming Heisenberg Uncertainity Principle to be true what could be the minimum uncertainty in
de-broglie wavelength of a moving electron accelerated by Potential Difference of 6 V whose uncertainty

7
in position is n.m.
22

(A) 6.25 Å (B) 6 Å (C) 0.625 Å (D) 0.3125 Å

8. A light source of wavelength  illuminates a metal and ejects photo-electrons with (KE)max = 1 eV.

Another light source of wavelength, , ejects photo-electrons from same metal with
3
(KE)max = 4 eV. Find the value of work function ?
(A) 1 eV (B) 2 eV (C) 0.5 eV (D) None of these
(ii) One or more options correct Type
This section contains 5 multiple choice questions. Each question has four choices (A), (B), (C) and
(D) out of which ONE or MORE are correct. 4(–1)
9. When photons of energy 4.25 eV strike the surface of a metal 'A', the ejected photo electrons
if maximum kinetic energy have wavelength A. The maximum kinetic energy of photoelectrons
liberated from another metal 'B' by photons of energy 4.7 eV is 1.5 eV less than that of
photo electrons of metal A. If wavelength of photo electrons of metal B is twice than that
of photoelectron of 'A' then -
(A) Work function of A = 2.25 eV
(B) Work function of B = 4.2 eV
(C) Maximum (K.E.) of photoelectrons of 'A' = 2 eV
(C) Maximum (K.E.) of photoelectrons of 'B' = 2.75 eV

10. The orbital angular momentum of an electron in a single electron system is 3 h . Which of the follow-

ing angular momentum value (s) are not possible for this electron in Bohr orbit.
3h h 3h 2h
(A) (B) (C) (D)
2   
11. For He+ ion, select incorrect option(s) :
(A) Difference between radius of II & III Bohr's orbit is greater than that of III & IV Bohr orbit.
(B) Ratio of velocity of electron in III & IV Bohr's orbit is less then one.
(C) Energy difference between consecutive energy levels decreases continuously.
(D) Ratio of wavelength of least energetic and most energetic photon of lyman series is (3/4).
12. Which of the following orbitals has (have) two spherical nodes?
(A) 2s (B) 4p (C) 3d (D) 6 f
13. Orbitals in which the numbers of radial and angular nodes are equals?
(A) 3p (B) 4d (C) 5d (D) 6f

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 GUIDED REVISION ENTHUSIAST & LEADER
Target : JEE(Main + Advanced) - 2019 COURSE
(iii) Paragraph Type
This section contains 2 paragraphs , describing theory, experiment, data etc. 6 questions relate to
one paragraphs with two questions. Each question of a paragraph has only one correct answer among
the four choices (A), (B), (C) and (D). 3(0)
Paragraph for questions 14 to 16
The hydrogen-like species Li2+ is in a spherically symmetric state S1 with one radial node. Upon absorbing
light the ion undergoes transition to a state S2. The state S2 has one radial node and its energy is equal
to the ground state energy of the hydrogen atom.
14. The state S1 is :-
(A) 1s (B) 2s (C) 2p (D) 3s
15. Energy of the state S1 in units of the hydrogen atom ground state energy is :-
(A) 0.75 (B) 1.50 (C) 2.25 (D) 4.50
16. The orbital angular momentum quantum number of the state S2 is :-
(A) 0 (B) 1 (C) 2 (D) 3
Paragraph for question nos. 17 to 19
The location of electron inside the atom can be predicted by wave mechanical model which gives
wavefunction of orbitals represented as n,,m where n,, m represents quantum numbers sometimes,
 can be analysed as two separate components , radial and angular, represented as (r) and ()
respectively for H, the following expressions of n,,m are known
2r
[Where a0 is constant and  is na ]
0

3/2
2 1  1
1,0,0 
a 3/0 2
e  / 2
3,0,0 
9 3  a 0 
 6  6    e2  / 2

3/ 2 3/2
1 1 1 1
 2,0,0   2   e  / 2
3,1,0   4    e  / 2
2 2  a 0  9 3  a 0 
17. For 1 s orbital H-atom, the radial probability will be maximum at what radial distance from nucleus:
(A) r = 0 (at the nucleus) (B) r = 
(C) r = a0 (D) r = 2a0

18. At what radial distance will there be a spherical node for 3py orbital of hydrogen?
(A) r = 6a0 (B) r = 2a0 (C) r = 0 (D) data is insufficient.
19. Which of the following statements are incorrect w.r.t. (r) v/s r graph for H-atom
(A) For 1s orbital the graph will not intersect x - axis at finite distance.
(B) For 2s orbital, the graph will have one 'local minima' only.
(C) For 3s orbital, the graph will intersect x - axis at two distinct points.
(D) For 3p orbital, the graph will intersect x-axis at two non-zero distinct points.

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 GUIDED REVISION ENTHUSIAST & LEADER
Target : JEE(Main + Advanced) - 2019 COURSE
SECTION-III : (Matrix Type)
This Section contains 1 question. Question has four statements (A, B, C and D) given in Column I and
five statements (P, Q, R, S and T) in Column II. Any given statement in Column I can have correct
matching with ONE or MORE statement(s) given in Column II. For example, if for a given question,
statement B matches with the statements given in Q and R, then for the particular question, against
statement B, darken the bubbles corresponding to Q and R in the ORS.
1. Match the column -
Column-I Column-II
(A) l (P) Indicates the distance from nucleus
(B) s (Q) It can have only two possible values.
(C) m (R) Possible values are 0 to (n – 1)
(D) n (S) Indicates the possible orientations in space.
(T) Possible values are +l to –l including ‘Zero’
SECTION-IV : (Integer Value Correct Type)
This section contains 3 questions. The answer to each question is a single digit Integer, ranging from
0 to 9 (both inclusive) 4(–1)
1. If 4 times the most probable distance of electron of a 1s orbital in a unielectronic atom /ion is given by
0.529 Å then the atomic number of the unielectronic species will be.

 Z3   Zr / a0
[Given : Wave function of 1s orbital,    a 3  e where a0 = radius of first Bohr's orbital in
0

H  atom   52.9pm  and Z is atomic number of unielectrnic species ]

2. Find the number of spectral lines in Paschen series emitted by atomic H, when electron is excited from
ground state to 7th energy level returns back.
3. The figure shows a sample of H-atoms having electron revolving in higher orbit ‘n’.

If this electron makes transition from this orbit ‘n’ to ground state, No. of paschen lines emtted are.