ATOMIC STRUCTURE QUIZ-6

ATOMIC STRUCTURE QUIZ-6

Dear Readers,

As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background. 

Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced. 

Q1. Which of the following is correct?

•   _1 H^1 and _2 He^3 are isotopes
•   _6 C^14 and _7 N^14 are isotopes
•   _19 K^39 and _20 Ca^40 are isotones
•   _9 F^19 and _11 Na^24 are isodiaphers

Solution
Isotones are species which have equal number of neutrons. Neutrons in 〖_19〗K^39=39-19=20 Neutrons in 〖_20〗Ca^40=40-20=20

Q2.Which particle contains 2 neutrons and 1 proton?

•   _1 H^2
•   _2 He^4
•  _1 T^3
•   _1 D^2

Solution
Tritium contains 2 neutrons and 1 proton.

Q3.  The line spectrum observed when electron falls from the higher level into L-level is known as:

•   Balmer series
•  Paschen series
•  Bracket series
•  None of these

Solution
Fall of electron from higher level to L-level, (i.e., 2nd shell) gives Balmer series.

Q4.  [Cr(H_2 O)_6 ] Cl_3 (at. No. of Cr=24) has a magnetic moment of 3.83 B.M. The correct distribution of 3d electrons in the chromium of the complex:

•  3d_xy^1,3d_yz^1,3d_xz^1
•  3s_xy^1,3d_yz^1,3d_(z^2)^1
•  (3d_(x^2-y^2)^1 ),3d_(z^2)^1,3d_xz^1
•  3d_xy^1,(3d_(x^2-y^2)^1 ),3d_yz^1

Solution
Cr^(3+):1s^2,2s^2 2p^6,3s^2 3p^6 3d^3. The 3d_xy^1,3d_xz^1,3d_yz^1 has lower energy.

Q5.An improbable configuration is:

•  [Ar]3d^4,4s^2
•  [Ar]3d^5,4s^1
•  [Ar]3d^6,4s^2
•  [Ar]3d^10,4s^1

Solution
 Nearly half-filled orbitals tend to acquire exactly half-filled nature to attain lower energy level.

Q6. The 'm' value for an electron in an atom is equal to the number of m value for l=1. The electron may be present in

•  3d_(x^2-y^2 )
•  5f_(x(x^2-y^2))
•  4f_(x^3/z)
•  None of these

Solution
Total value of m=(2l+1)=3 for l=1 m=3 is for f-subshell orbitals

Q7.According to Bohr’s theory, the angular momentum of an electron in 5th orbit is

•  25 h/π
•  1.0 h/π
•  10 h/π
•  2.5 h/π

Solution
Angular momentum of an electron =mvr=nh/2π (n is orbit number) in 5th orbit=5h/2π=2.5h/π

Q8.The ratio of speed of γ-rays and X-rays is:

•  1
•  <1 span="">
•  >1
•  None of these

Solution
Both are waves of radiant energy.

Q9.If the speed of electron in the Bohr's first orbit of hydrogen atom is x, the speed of the electron in the third Bohr's orbit is:

•  x/9
•  x/3
•  3x
•  9x

Solution
u_n=u/n.

Q10. The ratio of radii of two nuclei with mass numbers 27 and 64 is

•  1/2
•  3/4
•  3/2
•  2/3

Solution
r_nucleus∝(mass no.)^(1/3)