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Structure of Atom — JEE Main & Advanced Chemistry PYQs

526 previous year questions from Structure of Atom with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

526 questionsChemistrySolutions on every page
1

The 2s and the 2p orbital energies of hydrogen atom are E_ 2s ( H ) and E_ 2p ( H ) , respectively. The 2s and the 2p orbital energies of lithium atom are E_ 2s ( Li ) and E_ 2p (

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X ^ a+ and Y ^ b+ are hydrogen-like species. The wavelength of light absorbed during the transition between the states with principal quantum numbers n = 1 and n = 2 of X ^ a+ is .

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Consider two radiations of wavelengths 1. ₁ = 2000 Å 2. ₂ = 6000 Å The ratio of the energies of these two radiations ( E₁ E₂ ) is ________ (Nearest integer).

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The Bohr radius of a hydrogen like species is 70.53 pm. The species and the stationary state (n) are respectively (Given : Hydrogen atom Bohr radius is 52.9 pm)

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If shortest wavelength of hydrogen atom in Lyman series is x , then longest wavelength in Balmer series of He ^+ is:

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Match the List-I with List-II List-I Orbital List-II Radial nodes and nodal plane A. 2s I. 1 Radial node + two nodal planes B. 3s II. 1 Radial node + one nodal plane C. 3p III. 2 R

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Which of the following statement(s) is/are true ? A. If two orbitals have the same value of (n + l) , the orbital with lower value of n will have lower energy. B. Energies of the o

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Arrange the following atomic orbitals of multi electron atoms in order of increasing energy. A. n = 3, l = 2, m = +1 B. n = 4, l = 0, m = 0 C. n = 6, l = 1, m = 0 D. n = 5, l = 1,

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Identify the correct statements from the following: A. Heisenberg uncertainty principle is applicable to electrons. B. The size of 2p_x orbital is less than the size of 3p_x orbita

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The species having identical radii according to the Bohr's theory are: A. H (first orbit) B. He^+ (first orbit) C. He^+ (Second orbit) D. Li²⁺ (first orbit) E. Be³⁺ (Second orbit)

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What is the ratio of wave number of first line (lowest energy line) of Balmer series of H atomic spectrum to first line of its Brackett series?

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Which of the following is correct set of 4 quantum numbers of 19^ th electron in Chromium (Atomic number = 24 ) in accordance with Aufbau principle?

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A monoatomic anion (A^-) has 45 neutrons and 36 electrons. Atomic mass, group in the periodic table and physical state at room temperature of the element (A) respectively are

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The surface of sodium metal is irradiated with radiation of wavelength x nm. The kinetic energy of ejected electrons is 2.8 10⁻²⁰ J. The work function of sodium is 2.3 eV. The valu

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What is the energy (in J atom ⁻¹ ) required for the following process? Li²⁺(g) Li³⁺(g) + e^- (Take the ionization energy for the H atom in the ground state as 2.18 10⁻¹⁸ J atom ⁻¹

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The wavelength of photon ' A ' is 400 nm. The frequency of photon ' B ' is 10¹⁶ ~s ⁻¹ . The wave number of photon ' C^ is 10⁴ ~cm ⁻¹ . The correct order of energy of these photons

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Two positively charged particles m ₁ and m ₂ have been accelerated across the same potential difference of 200 keV as shown below. [Given mass of m ₁=1 amu and m ₂=4 amu] The deBro

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The wave numbers of three spectral lines of H atom are considered. Identify the set of spectral lines belonging to Balmer series. ( R = Rydberg constant)

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Which of the following point in Figure 2 most accurately represents the nodal surface as shown in Figure 1?

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The wavelength of spectral line obtained in the spectrum of Li ²⁺ ion, when the transition takes place between two levels whose sum is 4 and difference is 2, is

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The hydrogen spectrum consists of several spectral lines in Lyman series ( L ₁, ~L ₂ , L ₃ ; L ₁ has lowest energy among Lyman series). Similarly it consists of several spectral li

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The work functions of two metals (M_ A . and .M_ B ) are in the 1: 2 ratio. When these metals are exposed to photons of energy 6 eV, the kinetic energy of liberated electrons of M_

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Identify the INCORRECT statements from the following: A. Notation ₁₂²⁴ Mg represents 24 protons and 12 neutrons. B. Wavelength of a radiation of frequency 4.5 10¹⁵ ~s ⁻¹ is 6.7 10⁻

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Given, (A) n =5, ~m ₁=-1 (B) n =3, l =2, ~m ₁=-1, ~m _ s =+ 1 2 The maximum number of electron(s) in an atom that can have the quantum numbers as given in (A) and (B) respectively

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Which of the following statements regarding the energy of the stationary state is true in the following one - electron systems ?

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The energy of first (lowest) Balmer line of H atom is x ~J . The energy (in J) of second Balmer line of H atom is :

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The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is _ _ _ _ J mol ⁻¹ . Given: R_ H =2.18 10⁻¹¹ ergs .

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Consider the following spectral lines for atomic hydrogen : A. First line of Paschen series B. Second line of Balmer series C. Third line of Paschen series D. Fourth line of Bracke

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Given below are two statements : Statement I : When an electric discharge is passed through gaseous hydrogen, the hydrogen molecules dissociate and the energetically excited hydrog

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The energy of an electron in first Bohr orbit of H -atom is -13.6 eV. The magnitude of energy value of electron in the first excited state of Be ³⁺ is ________ eV. (nearest integer

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Correct statements for an element with atomic number 9 are A. There can be 5 electrons for which m _ s =+ 1 2 and 4 electrons for which m _ s =- 1 2 B. There is only one electron i

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The extra stability of half-filled subshell is due to (A) Symmetrical distribution of electrons (B) Smaller coulombic repulsion energy (C) The presence of electrons with the same s

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Which of the following statements are correct, if the threshold frequency of caesium is 5.16 10¹⁴ ~Hz ? A. When Cs is placed inside a vacuum chamber with an ammeter connected to it

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Consider the ground state of chromium atom ( Z =24) . How many electrons are with Azimuthal quantum number l=1 and l=2 respectively ?

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Which one of the following about an electron occupying the 1 s orbital in a hydrogen atom is incorrect ? (Bohr's radius is represented by a a₀ )

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For electron in ' 2 s ' and ' 2 p ' orbitals, the orbital angular momentum values, respectively are :

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Which of the following postulate of Bohr's model of hydrogen atom in not in agreement with quantum mechanical model of an atom ?

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Which of the following statements are true? (A) The subsidiary quantum number l describes the shape of the orbital occupied by the electron. (B) is the boundary surface diagram of

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According to Bohr's model of hydrogen atom, Which of the following statements is incorrect?

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For hydrogen like species, which of the following graphs provides the most appropriate representation of E vs Z plot for a constant n ? [E: Energy of the stationary state, Z : atom

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The calculated spin-only magnetic moments of K ₃ [ Fe ( OH )₆ ] and K ₄ [ Fe ( OH )₆ ] respectively are :

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Given below are two statements : Statement (I) : It is impossible to specify simultaneously with arbitrary precision, both the linear momentum and the position of a particle. State

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Given below are two statements : Statement ( ( I )): The radii of isoelectronic species increases in the order. ( Mg ²⁺ Na ⁺ F ⁻ O ²⁻ ) Statement (II): The magnitude of electron ga

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If ( a ₀ ) is denoted as the Bohr radius of hydrogen atom, then what is the de-Broglie wavelength (( ) ) of the electron present in the second orbit of hydrogen atom? [n : any inte

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Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom? (A) 1 ~s 2 p 3 ~d 4 ~s (B) 1 ~s 2 ~s =2 p 3 ~s =3 p (C) 1 ~s 2 ~s 2 p 3 ~s 3 p

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In a multielectron atom, which of the following orbitals described by three quantum numbers will have same energy in absence of electric and magnetic fields? A. n =1, l =0, ~m ₁=0

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For hydrogen atom, the orbital/s with lowest energy is/are : (A) 4 s (B) 3 p _x (C) 3 ~d _ x^2-y^2 (D) 3 ~d _ z^2 (E) 4 p _z Choose the correct answer from the options given below

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Given below are two statements : Statement (I) : For a given shell, the total number of allowed orbitals is given by n ^2 . Statement (II) : For any subshell, the spatial orientati

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Given below are two statements about X-ray spectra of elements : Statement (I) : A plot of v ( v= frequency of X -rays emitted) vs atomic mass is a straight line. Statement (II) :

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Heat treatment of muscular pain involves radiation of wavelength of about 900 nm . Which spectral line of H atom is suitable for this? Given : Rydberg constant R _ H =10^5 ~cm ⁻¹,

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Given below are two statements : Statement (I) : A spectral line will be observed for a 2 p _x 2 p _y transition. Statement (II) : 2 P_x and 2 p_y are degenerate orbitals. In the l

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Radius of the first excited state of Helium ion is given as : a ₀ radius of first stationary state of hydrogen atom.

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According to Bohr's model, the highest kinetic energy is associated with the electron in the

JEE Advanced 2024 Solution View → 54

Among the following, the correct statement(s) for electrons in an atom is(are)

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The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency ' ( A ) ' ( 10¹² ) hertz and that has a radiant intensity i

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The electronic configuration of Einsteinium is : (Given atomic number of Einsteinium (=99) )

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Match List I with List II ( array |l|l|l|l| & List - I (Element) & & List - II (Electronic configuration) A. & N & I. & [ Ar ] 3 ~d ¹⁰ 4 ~s ^2 4 p ^5 AR B. & S & II. & [ Ne ] 3 ~s

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Based on Heisenberg's uncertainty principle, the uncertainty in the velocity of the electron to be found within an atomic nucleus of diameter (10⁻¹⁵ ~m ) is ________. (10^9 ~ms ⁻¹

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Compare the energies of following sets of quantum numbers for multielectron system. (A) ( n =4,1=1 ) (B) ( n =4, l =2 ) (C) ( n =3,1=1 ) (D) ( n =3,1=2 ) (E) ( n =4,1=0 ) Choose th

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Wavenumber for a radiation having (5800 Ã… ) wavelength is (x 10 ~cm ⁻¹ ). The value of (x ) is ________ (Integer answer)

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A hypothetical electromagnetic wave is show below. The frequency of the wave is (x 10¹⁹ ~Hz ). (x = ) ______ (nearest integer)

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Consider the following reactions ( NiS + HNO ₃+ HCl A + NO + S + H ₂ O ) ( aligned A + NH ₄ OH + H ₃ C - C & = N - OH | ~ H ₃ C - C & = N - OH aligned B + NH ₄ Cl + H ₂ O ) The num

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For hydrogen atom, energy of an electron in first excited state is (-3.4 eV , K . E ). of the same electron of hydrogen atom is (x eV ). Value of (x ) is ______ ( 10⁻¹ eV ). (Neare

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Frequency of the de-Broglie wave of electron in Bohr's first orbit of hydrogen atom is _______ ( 10¹³ ~Hz ) (nearest integer). ( aligned & [Given : R _ H ( Rydberg constant )=2.18

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In an atom, total number of electrons having quantum numbers ( n =4, | ~m _l |=1 ) and ( m _ s =- 1 2 ) is ______

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The incorrect postulates of the Dalton's atomic theory are : (A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when a

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The value of Rydberg constant ( (R_H ) ) is (2.18 10⁻¹⁸ ~J ). The velocity of electron having mass (9.1 10⁻³¹ ~kg ) in Bohr's first orbit of hydrogen atom (= ) _______ ( 10^5 ~ms ⁻

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Choose the Incorrect Statement about Dalton's Atomic Theory

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The maximum number of orbitals which can be identified with ( n =4 ) and (m_l=0 ) is ______

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The de-Broglie's wavelength of an electron in the (4^ th ) orbit is ( ) ( a ₀ ( a ₀= . ) Bohr's radius () )

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The number of radial node/s for 3 p orbital is:

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According to the wave-particle duality of matter by de-Broglie, which of the following graph plot presents most appropriate relationship between wavelength of electron λ and moment

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The four quantum numbers for the electron in the outer most orbital of potassium (atomic no. 19 ) are

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The ionization energy of sodium in kJ mol – 1 . If electromagnetic radiation of wavelength 242 nm is just sufficient to ionize sodium atom is ______.(nearest integer)

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Number of spectral lines obtained in He + spectra, when an electron makes transition from fifth excited state to first excited state will be

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Given below are two statements: Statement-I: The orbitals having same energy are called as degenerate orbitals. Statement-II: In hydrogen atom, 3 p and 3 d orbitals are not degener

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Match List I with List II Choose the correct answer from the options given below :-

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The correct set of four quantum numbers for the valence electron of rubidium atom ( Z = 37 ) is:

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Total number of ions from the following with noble gas configuration is Sr 2 + ( Z = 38 ) , Cs + ( Z = 55 ) , La 2 + ( Z = 57 ) Pb 2 + ( Z = 82 ) , Yb 2 + ( Z = 70 ) and Fe 2 + ( Z

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The electronic configuration for Neodymium is: [Atomic Number for Neodymium 60]

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Which of the following electronic configuration would be associated with the highest magnetic moment ?

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The number of electrons present in all the completely filled subshells having n = 4 and s = + 1 2 is ____ (Where n = principal quantum number and s = spin quantum number)

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For He + , a transition takes place from the orbit of radius 105 . 8 pm to the orbit of radius 26 . 45 pm . The wavelength (in nm ) of the emitted photon during the transition is B

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Given below are two statements Statement I : According to Bohr’s model of hydrogen atom, the angular momentum of an electron in a given stationary state is quantised. Stateme

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The total number of isoelectronic species from the given set is ________. O 2 - , F – , Al , Mg 2 + , Na + , O + , Mg , Al 3 + , F

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The orbital angular momentum of an electron in 3 s orbital is xh 2 π . The value of x is (nearest integer)

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The energy of an electron in the first Bohr orbit of hydrogen atom is - 2 . 18 × 10 - 18 J Its energy in the third Bohr orbit is _ _ _ _ _ _ _ .

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Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R Assertion A : 5 f electron can participate in bonding to a far greater extent t

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Values of work function ( W 0 ) for a few metals are given below Metal Li Na K Mg Cu Ag W 0 eV 2 . 42 2 . 3 2 . 25 3 . 7 4 . 8 4 . 3 The number of metals which will show photoelect

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The number of correct statements from the following is ........... A. For 1 s orbital, the probability density is maximum at the nucleus B. For 2 s orbital, the probability density

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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : Assertion A: In the photoelectric effect, the electrons are ejected from the

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The electron in the n th orbit of Li 2 + is excited to ( n + 1 ) orbit using the radiation of energy 1 . 47 × 10 - 17 J (as shown in the diagram). The value of n is __________

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For a metal ion, the calculated magnetic moment is 4 . 90 BM . This metal ion has _______ number of unpaired electrons

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Henry Moseley studied characteristic X -ray spectra of elements. The graph which represents his observation correctly is Given v = Frequency of X-ray emitted Z = Atomic number

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The number of atomic orbitals from the following having 5 radial nodes is 7 s ,   7 p ,   6 s ,   8 p ,   8 d

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The number of following statement/s which is/are incorrect is ______ A) Line emission spectra are used to study the electronic structure B) The emission spectra of atoms in the gas

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If the radius of the first orbit of hydrogen atom is a 0 , then de Broglie’s wavelength of electron in 3 rd orbit is

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The wavelength of an electron of kinetic energy 4 . 50 × 10 - 29 J is ________ × 10 – 5 m . (Nearest integer) Given: mass of electron is 9 × 10 – 31 kg ,

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Which one of the following sets of ions represents a collection of isoelectronic species? (Given : Atomic Number : F : 9 , Cl : 17 , Na = 11 Mg = 12 , Al = 13 , K = 19 , Ca = 20 ,

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Electrons in a cathode ray tube have been emitted with a velocity of 1000   ms - 1 . The number of following statements which is/are true about the emitted radiation is Given

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Arrange the following orbitals in decreasing order of energy. A. n = 3 , l = 0 , m = 0 B. n = 4 , l = 0 , m = 0 C. n = 3 , l = 1 , m = 0 D. n = 3 , l = 2 , m = 1 The correct option

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Which transition in the hydrogen spectrum would have the same wavelength as the Balmer type transition from n = 4 to n = 2 of He + spectrum

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The wave function Ψ of 2 s is given by Ψ 2 s = 1 2 2 π 1 a 0 1 / 2 2 - r a 0 e - r / 2 a 0 At r = r 0 , radial node is formed. Thus, r 0 in terms of a 0

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Maximum number of electrons that can be accommodated in shell with n = 4 are:

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The energy of one mole of photons of radiation of frequency 2 × 10 12 Hz in Jmol - 1 is _____ . (Nearest integer) (Given: h = 6 . 626 × 10 - 34 Js N A = 6 . 022 × 10

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Assume that the radius of the first Bohr orbit of hydrogen atom is 0 . 6 Å . The radius of the third Bohr orbit of He + is _____ picometer. (Nearest Integer)

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The shortest wavelength of hydrogen atom in Lyman series is λ . The longest wavelength in Balmer series of He + is

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The number of given orbitals which have electron density along the axis is p x , p y , p z , d xy , d yz , d xz , d z 2 , d x 2 - y 2

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The radius of the 2 nd orbit of Li 2 + is x . The expected radius of the 3 rd orbit of Be 3 + is

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Following figure shows spectrum of an ideal black body at four different temperatures. The number of correct statement/s from the following is _______. A. T 4 > T 3 > T 2 > T 1 B.

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It is observed that characteristic X-ray spectra of elements show regularity. When frequency to the power 'n' i.e. v n of X-rays emitted is plotted against atomic number Z

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If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm , then the wavelength of the second line of this series is _______ nm . (Nearest integer)

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Given below are the quantum numbers for 4 electrons. A. n = 3 , l = 2 , m 1 = 1 , m s = + 1 2 B. n = 4 , l = 1 , m 1 = 0 , m s = + 1 2 C. n = 4 , l = 2 , m 1 = - 2 , m s = - 1 2 D.

JEE Main 2022 Solution View → 114

The minimum uncertainty in the speed of an electron in one dimensional region of length 2 a o (Where a o = Bohr radius 52 . 9 pm ) is____ kms - 1 (Nearest integer) (Given : Mass of

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Which of the following pair is not isoelectronic species? (Atomic numbers Sm = 62 ; Er = 68 ; Yb = 70 ; Lu = 71 ; Eu = 63 ; Tb = 65 ; Tm = 69 )

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If the wavelength for an electron emitted from H - atom is 3 . 3 × 10 - 10 m , then energy absorbed by the electron in its ground state compared to minimum energy required for

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Identify the incorrect statement from the following.

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The correct decreasing order of energy, for the orbitals having, following set of quantum numbers: (A) n = 3 , 1 = 0 , m = 0 (B) n = 4 , l = 0 , m = 0 (C) n = 3 , l = 1 , m = 0 (D)

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Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R . Assertion A : Energy of 2 s orbital of hydrogen atom is greater than that of

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Consider an imaginary ion X 3 - 22 48 . The nucleus contains ' a ' % more neutrons than the number of electrons in the ion. The value of ' a ' is

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