MCQOPTIONS
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MCQOPTIONS
This section includes 29 Mcqs, each offering curated multiple-choice questions to sharpen your Chemistry knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The proton and neutron are collectively called as [MP PET 2001] |
| A. | Deutron |
| B. | Positron |
| C. | Meson |
| D. | Nucleon |
| Answer» E. | |
| 2. |
The average distance of an electron in an atom from its nucleus is of the order of [MP PET 1996] |
| A. | \[{{10}^{6}}m\] |
| B. | \[{{10}^{-6}}m\] |
| C. | \[{{10}^{-10}}m\] |
| D. | \[{{10}^{-15}}m\] |
| Answer» D. \[{{10}^{-15}}m\] | |
| 3. |
The size of nucleus is of the order of [CPMT 1982; MP PMT 1991] |
| A. | \[{{10}^{-12}}m\] |
| B. | \[{{10}^{-8}}m\] |
| C. | \[{{10}^{-15}}m\] |
| D. | \[{{10}^{-10}}m\] |
| Answer» D. \[{{10}^{-10}}m\] | |
| 4. |
The size of nucleus is measured in [EAMCET 1988; CPMT 1994] |
| A. | amu |
| B. | Angstrom |
| C. | Fermi |
| D. | cm |
| Answer» D. cm | |
| 5. |
Anode rays were discovered by [DPMT 1985] |
| A. | Goldstein |
| B. | J. Stoney |
| C. | Rutherford |
| D. | J.J. Thomson |
| Answer» B. J. Stoney | |
| 6. |
The nucleus of helium contains [CPMT 1972; DPMT 1982] |
| A. | Four protons |
| B. | Four neutrons |
| C. | Two neutrons and two protons |
| D. | Four protons and two electrons |
| Answer» D. Four protons and two electrons | |
| 7. |
Cathode rays are[JIPMER 1991; NCERT 1976] |
| A. | Protons |
| B. | Electrons |
| C. | Neutrons |
| D. | \[\alpha \]-particles |
| Answer» C. Neutrons | |
| 8. |
The number of nodal planes in a \[{{p}_{x}}\] is [IIT Screening 2000] |
| A. | One |
| B. | Two |
| C. | Three |
| D. | Zero |
| Answer» B. Two | |
| 9. |
The Bohr orbit radius for the hydrogen atom \[(n=1)\] is approximately \[0.530{AA}\]. The radius for the first excited state \[(n=2)\] orbit is [CBSE PMT 1998; BHU 1999] |
| A. | \[0.13{AA}\] |
| B. | \[1.06{AA}\] |
| C. | \[4.77{AA}\] |
| D. | \[2.12{AA}\] |
| Answer» E. | |
| 10. |
Number of neutrons in heavy hydrogen atom is [MP PMT 1986] |
| A. | 0 |
| B. | 1 |
| C. | 2 |
| D. | 3 |
| Answer» C. 2 | |
| 11. |
An element have atomic weight 40 and it?s electronic configuration is \[1{{s}^{2}}2{{s}^{2}}2{{p}^{6}}3{{s}^{2}}3{{p}^{6}}.\] Then its atomic number and number of neutrons will be [RPMT 2002] |
| A. | 18 and 22 |
| B. | 22 and 18 |
| C. | 26 and 20 |
| D. | 40 and 18 |
| Answer» B. 22 and 18 | |
| 12. |
The present atomic weight scale is based on [EAMCET 1988; MP PMT 2002] |
| A. | \[{{C}^{12}}\] |
| B. | \[{{O}^{16}}\] |
| C. | \[{{H}^{1}}\] |
| D. | \[{{C}^{13}}\] |
| Answer» B. \[{{O}^{16}}\] | |
| 13. |
\[Ca\] has atomic no. 20 and atomic weight 40. Which of the following statements is not correct about \[Ca\]atom [MP PET 1993] |
| A. | The number of electrons is same as the number of neutrons |
| B. | The number of nucleons is double of the number of electrons |
| C. | The number of protons is half of the number of neutrons |
| D. | The number of nucleons is double of the atomic number |
| Answer» D. The number of nucleons is double of the atomic number | |
| 14. |
\[N{{a}^{+}}\]ion is isoelectronic with [CPMT 1990] |
| A. | \[L{{i}^{+}}\] |
| B. | \[M{{g}^{+2}}\] |
| C. | \[C{{a}^{+2}}\] |
| D. | \[B{{a}^{+2}}\] |
| Answer» C. \[C{{a}^{+2}}\] | |
| 15. |
Which of the following particles has more electrons than neutrons |
| A. | \[C\] |
| B. | \[{{F}^{-}}\] |
| C. | \[{{O}^{-2}}\] |
| D. | \[A{{l}^{+3}}\] |
| Answer» D. \[A{{l}^{+3}}\] | |
| 16. |
The atomic number of an element represents [CPMT 1983; CBSE PMT 1990; NCERT 1973; AMU 1984] |
| A. | Number of neutrons in the nucleus |
| B. | Number of protons in the nucleus |
| C. | Atomic weight of element |
| D. | Valency of element |
| Answer» C. Atomic weight of element | |
| 17. |
A sodium cation has different number of electrons from |
| A. | \[{{O}^{2-}}\] |
| B. | \[{{F}^{-}}\] |
| C. | \[L{{i}^{+}}\] |
| D. | \[A{{l}^{+3}}\] |
| Answer» D. \[A{{l}^{+3}}\] | |
| 18. |
The energy of electron in hydrogen atom in its grounds state is ?13.6 eV. The energy of the level corresponding to the quantum number equal to 5 is [Pb. CET 2002] |
| A. | ?0.54 eV |
| B. | ? 0.85 eV |
| C. | ? 0.64 eV |
| D. | ? 0.40 eV |
| Answer» B. ? 0.85 eV | |
| 19. |
Ratio of radii of second and first Bohr orbits of H atom [BHU 2003] |
| A. | 2 |
| B. | 4 |
| C. | 3 |
| D. | 5 |
| Answer» C. 3 | |
| 20. |
Bohr model of atom is contradicted by [MP PMT 2002] |
| A. | Pauli?s exclusion principle |
| B. | Planck quantum theory |
| C. | Heisenberg uncertainty principle |
| D. | All of these |
| Answer» D. All of these | |
| 21. |
The formation of energy bonds in solids are in accordance with [DCE 2001] |
| A. | Heisenberg?s uncertainty principle |
| B. | Bohr?s theory |
| C. | Ohm?s law |
| D. | Rutherford?s atomic model |
| Answer» C. Ohm?s law | |
| 22. |
If change in energy \[(\Delta E)=3\times {{10}^{-8}}J,\,\,h=6.64\times {{10}^{-34}}J\text{-}s\] and \[c=3\times {{10}^{8}}\,m/s,\] then wavelength of the light is [CBSE PMT 2000] |
| A. | \[6.36\times {{10}^{3}}\text{{ }\!\!\mathrm{\AA}\!\!\text{ }}\] |
| B. | \[6.36\times {{10}^{5}}\text{{ }\!\!\mathrm{\AA}\!\!\text{ }}\] |
| C. | \[6.64\times {{10}^{-8}}\text{{ }\!\!\mathrm{\AA}\!\!\text{ }}\] |
| D. | \[6.36\times {{10}^{18}}\text{{ }\!\!\mathrm{\AA}\!\!\text{ }}\] |
| Answer» D. \[6.36\times {{10}^{18}}\text{{ }\!\!\mathrm{\AA}\!\!\text{ }}\] | |
| 23. |
Radius of the first Bohr's orbit of hydrogen atom is [RPET 2000] |
| A. | \[1.06\,{AA}\] |
| B. | \[0.22\,{AA}\] |
| C. | \[0.28\,{AA}\] |
| D. | \[0.53\,{AA}\] |
| Answer» E. | |
| 24. |
In hydrogen spectrum the different lines of Lyman series are present is [UPSEAT 1999] |
| A. | UV field |
| B. | IR field |
| C. | Visible field |
| D. | Far IR field |
| Answer» B. IR field | |
| 25. |
The element used by Rutherford in his famous scattering experiment was [KCET 1998] |
| A. | Gold |
| B. | Tin |
| C. | Silver |
| D. | Lead |
| Answer» B. Tin | |
| 26. |
An electronic transition from 1s orbital of an atom causes [JIPMER 1997] |
| A. | Absorption of energy |
| B. | Release of energy |
| C. | Both release or absorption of energy |
| D. | Unpredictable |
| Answer» B. Release of energy | |
| 27. |
The expression for Bohr's radius of an atom is [MP PMT 1999] |
| A. | \[r=\frac{{{n}^{2}}{{h}^{2}}}{4{{\pi }^{2}}m{{e}^{4}}{{z}^{2}}}\] |
| B. | \[r=\frac{{{n}^{2}}{{h}^{2}}}{4{{\pi }^{2}}m{{e}^{2}}z}\] |
| C. | \[r=\frac{{{n}^{2}}{{h}^{2}}}{4{{\pi }^{2}}m{{e}^{2}}{{z}^{2}}}\] |
| D. | \[r=\frac{{{n}^{2}}{{h}^{2}}}{4{{\pi }^{2}}{{m}^{2}}{{e}^{2}}{{z}^{2}}}\] |
| Answer» C. \[r=\frac{{{n}^{2}}{{h}^{2}}}{4{{\pi }^{2}}m{{e}^{2}}{{z}^{2}}}\] | |
| 28. |
The energy of second Bohr orbit of the hydrogen atom is ?328 kJ mol?1, hence the energy of fourth Bohr orbit would be [CBSE PMT 2005] |
| A. | ? 41 kJ mol?1 |
| B. | ?1312 kJ mol?1 |
| C. | ?164 kJ mol?1 |
| D. | ? 82 kJ mol?1 |
| Answer» E. | |
| 29. |
Which one of the following is not the characteristic of Planck's quantum theory of radiation [AIIMS 1991] |
| A. | The energy is not absorbed or emitted in whole number or multiple of quantum |
| B. | Radiation is associated with energy |
| C. | Radiation energy is not emitted or absorbed conti- nuously but in the form of small packets called quanta |
| D. | This magnitude of energy associated with a quantum is proportional to the frequency |
| Answer» B. Radiation is associated with energy | |