1
JEE Main 2020 (Online) 8th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The radius of the second Bohr orbit, in terms of the Bohr radius, a0, in Li2+ is :
A
$${{2{a_0}} \over 9}$$
B
$${{2{a_0}} \over 3}$$
C
$${{4{a_0}} \over 9}$$
D
$${{4{a_0}} \over 3}$$
2
JEE Main 2020 (Online) 8th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Hydrogen has three isotopes (A), (B) and (C). If the number of neutron(s) in (A), (B) and (C) respectively, are (x), (y) and (z), the sum of (x), (y) an (z) is :
A
3
B
1
C
4
D
2
3
JEE Main 2020 (Online) 8th January Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For the Balmer series in the spectrum of H atom,
$$\overline \nu = {R_H}\left\{ {{1 \over {n_1^2}} - {1 \over {n_2^2}}} \right\}$$, the correct statements among (I) to (IV) are :
(I) As wavelength decreases, the lines in the series converge
(II) The integer n1 is equal to 2
(III) The lines of longest wavelength corresponds to n2 = 3
(IV) The ionization energy of hydrogen can be calculated from wave number of these lines
A
(II), (III), (IV)
B
(I), (II), (III)
C
(I), (III), (IV)
D
(I), (II), (IV)
4
JEE Main 2020 (Online) 7th January Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The number of orbitals associated with quantum number n = 5, ms = +$${1 \over 2}$$ is :
A
11
B
25
C
15
D
50
JEE Main Subjects
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
CBSE
Class 12