Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Structure of Atom question

2022 · 26 Jun · Shift 1 · Q2
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Chemistry
  4. /Structure of Atom
  5. /2022 · 26 Jun · Shift 1 · Q2

Structure of Atom question

2022 · 26 Jun · Shift 1 · Q2

JEE MainChemistryStructure of AtomMCQ+4 / −1
If the radius of the 3rd Bohr's orbit of hydrogen atom is r3 and the radius of 4th Bohr's orbit is r4. Then :
  1. A
    r4=916r3{r_4} = {9 \over {16}}{r_3}r4​=169​r3​
  2. B
    r4=169r3{r_4} = {16 \over {9}}{r_3}r4​=916​r3​
  3. C
    r4=34r3{r_4} = {3 \over {4}}{r_3}r4​=43​r3​
  4. D
    r4=43r3{r_4} = {4 \over {3}}{r_3}r4​=34​r3​
View written solutionFree

Correct answer: B

  1. Bohr radius formula

    For the hydrogen atom, the radius of the nthn^{\text{th}}nth Bohr orbit is rn=a0n2r_n = a_0 n^2rn​=a0​n2 where a0a_0a0​ is the Bohr radius.

  2. Write expressions for r3r_3r3​ and r4r_4r4​

    For the 3rd orbit: r3=a0(3)2=9a0r_3 = a_0 (3)^2 = 9a_0r3​=a0​(3)2=9a0​

    For the 4th orbit: r4=a0(4)2=16a0r_4 = a_0 (4)^2 = 16a_0r4​=a0​(4)2=16a0​

  3. Find the relation between r4r_4r4​ and r3r_3r3​

    r4r3=16a09a0=169\frac{r_4}{r_3} = \frac{16a_0}{9a_0} = \frac{16}{9}r3​r4​​=9a0​16a0​​=916​

    Therefore, r4=169r3r_4 = \frac{16}{9}r_3r4​=916​r3​

  4. Check options

    • A: r4=916r3r_4 = \frac{9}{16}r_3r4​=169​r3​ ❌
    • B: r4=169r3r_4 = \frac{16}{9}r_3r4​=916​r3​ ✅
    • C: r4=34r3r_4 = \frac{3}{4}r_3r4​=43​r3​ ❌
    • D: r4=43r3r_4 = \frac{4}{3}r_3r4​=34​r3​ ❌

Hence, the correct option is B.

PreviousNext

More from Structure of Atom

  • The number of radial and angular nodes in 4d orbital are, respectively2022 · MCQ
  • Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Energy of 2s orbital of hydrogen atom is greater than that of 2s orbital of lithium. Reason R:…2022 · MCQ
  • The correct decreasing order of energy for the orbitals having, following set of quantum numbers : (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 is :2022 · MCQ
  • Outermost electronic configurations of four elements A, B, C, D are given below : (A) 3s2(B) 3s23p1(C) 3s23p3(D) 3s23p4 The correct order of first ionization enthalpy for them is :2022 · MCQ
  • If the uncertainty in velocity and position of a minute particle in space are, 2.4 × 10 − 26 (m s − 1) and 10 − 7 (m) respectively. The mass of the particle in g is ​. (Nearest integer) (Given : h =…2022 · Numerical
  • Consider the following set of quantum numbers. The number of correct sets of quantum numbers is ​. Includes table2022 · Numerical
  • Identify the incorrect statement from the following.2022 · MCQ
  • Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R Assertion A: Zero orbital overlap is an out of phase overlap. Reason R : It results due to…2022 · MCQ