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This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The value of magnetic moment is zero in the case of antiferromagneticsubstances because the domains _______ |
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Answer» getoriented in the direction of the applied MAGNETIC FIELD |
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| 2. |
Two litresof an ideal gas at a pressure of 10 atmexpands Isothermally into vacuum until its total volumeis 10 litres. How muach heat is absorbed and howmuch work is done in the expansion ?What would be the heatabsorbed andwork done (i) if the same expansion takes place against a constant external pressureof 1 atm ? (ii) if the same expansion takes place to a final volume of 10 litres conducted reversibly? |
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Answer» Solution :For isothermal expansion of an ideal gas,` Delta U = 0` `:. q = -w= P_(ext) ( 10L-2L) = 0 (8) = 0` (i) ` q= - w = 1 ATM xx 8 L = 8 L atm = 8 xx 101.3 J = 810.4 J ( 1L atm = 101. 3 J )` (ii) `q= -w= 2.303 RT log. (V_(2))/(V_(1)) = 2.303 PV log . (V_(2))/(V_(1)) = 2.303 xx 10 atm xx 2 L log. (10)/(2) = 32. 2 L atm.` `= 32.2 xx 101 . 3 J = 3261.86J` |
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| 3. |
Which has the smallest bond-length- |
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Answer» `O_(2)^(+)` |
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| 4. |
The value of four quantum numbers for a 4d electrons will be |
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Answer» 4,3,2,+1/2 |
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| 5. |
Which of the following compound is metallic andferromagnetic ? |
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Answer» `CrO_(2)` |
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| 6. |
Which of the following conclusions could not be derived from Rutherford's prop- particle scattering experiment? |
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Answer» Most of the space in the atom is empty. |
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| 7. |
What is the volume of 1 g hydrogen gas at STP ? |
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Answer» 11.2 L |
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| 8. |
Which of the following statements is not true about potash alum ? |
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Answer» Its empirical formula is `KAL(SO_(4))_(2).12H_(2)O` |
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| 9. |
What must be the velocity of a beam of electrons if they are to disply a de Broglie wavelength of 100 Å (mass of electron = 9.1 xx 10^(-31) kg, h = 6.6 xx 10^(-34) J s)? |
| Answer» SOLUTION :`7.25 xx 10^(4) ms^(-1)` | |
| 10. |
When electron enters into the orbital of equal energy subshells, they are arranged in such a way that the direction of their spins remain parallel or the value of spin quantum number remains maximum. This statement is known as… |
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Answer» HUND’s rule |
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| 11. |
Which of the following compounds possess the maximum number of pi-bonds? |
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Answer» Formaldehyde 
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| 12. |
Which of the following is the most activating in electrophilic aromatic substitution? -NO_2 "" - NH_2 ""-NHCOCH_3 ""-CN |
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Answer» `-NO_2` |
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| 13. |
What is demineralized water? How is it obtained ? |
| Answer» SOLUTION :Water which does not contain more DISSOLVED cations and ANIONS is called demineralised water. It is obtained by PASSING ordinary water first through CATION exchangeresin. | |
| 14. |
What is the best possible arrangement of four bond pairs in the valence shell of an atom to minimise repulsions ? |
| Answer» SOLUTION :TETRAHEDRAL | |
| 15. |
Which of the following reaction will yields 2,2-dibromopropane ? |
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Answer» `CH_3-CH= CH_2 + HBR to ` |
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| 16. |
Which of the following oxide cannot be reduced to metal by carbon ? |
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Answer» CuO |
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| 17. |
Which of the following isomeric heptanes can yield seven differentt monochlorinated products upon free radical chlorination? |
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Answer» 2,2-Dimethylpentane `H_(3)C-CH_(2)-CH_(2)-overset(CH_(3))overset(|)(C)H-CH_(2)-CH_(3)` Each CARBON ATOM on chlorination gives a different products. |
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| 18. |
Which of the following contains maximum enol form ? |
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Answer»
 GROUPS are STRONG -I groups hence METHYLENE .H. is more ACIDIC.
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| 19. |
Why boron halides do not exist as dimers while AlCl_(3) exist as Al_(2)Cl_(6) ? |
| Answer» SOLUTION :Boronatom beingsmall in sizeis unableto accommodate FOUR largesizedhalogen ATOMS (exept F) aroundit. G HOWEVER, because of biggersize, Al can easily accommodatefour big sizedCl atomsaround it. Since in AlCl_(3), there areonly six electrons aroundAl atom, therefore, it completesits octet by ACCEPTING a lone pair of electronsfrom Cl atom ofanother `AlCl_(3)` molecule. As a result, `AlCl_(3)` existsas a chlorinebridgeddimericstructure. | |
| 20. |
What do you understand by decarboxylation of an acid ? |
| Answer» Solution :Decarboxylation is a chemical reaction that removes a carboxyl group and RELEASES carbon DIOXIDE `(CO_2)` . Usually, decarboxylation refers to a reaction of carboxylic ACIDS, removing a carbon atom from a carbon CHAIN. | |
| 21. |
The Weiss indices of a plane are 1/2, 1/2, 1/2. Its miller indices will be -----and the plane is designated as ---------. |
| Answer» SOLUTION : 2, 2, 2, (222) PLANE | |
| 22. |
Tyrosine is one of the amino acids present in protein. Its content in the protein is 0.22% and its molecular weight is 181 g mol^(-1). What is the lowest molecular weight of the protein? |
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Answer» |
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| 23. |
Which of the following electronic configuration is not possible? |
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Answer» `1s^2 2s^2 2p^6` |
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| 24. |
The solvay process can be represented by the following scheme: Identity A, B, C, D and E. |
| Answer» SOLUTION :`A=Ca(OH)_(2), B=NH_(4)HCO_(3), C=Na_(2)CO_(3), D=NH_(4)Cl, E=CaCl_(2)` | |
| 25. |
Which of the following chemical is used instead of using C_2Cl_4, in the dry cleaning process |
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Answer» LIQUIFIED `CO_2` |
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| 26. |
What is the molality ofa 10%W/W aqueous sodium hydroxide solution? |
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Answer» `2.778` Molality `= ("No. of moles of solute")/("Weight of solvent (in kg)")= (((10)/(40)))/(0.1)= (0.25)/(0.1) = 2.5 M` |
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| 27. |
What are the equivalent volumes of hydrogen, oxygen and nitrogen? |
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Answer» SOLUTION :Equivalent volume is the volume occupied by one equivalent of any GAS at NTP. We know, 1 mole of molecules of any gas at NTP occupies 22-4 litres and 1 mole of atoms of any diatomic gas at NTP occupies 11-2 litres. Now, 1 mole of H contains 1 equivalent of H, 1 mole of O contains 2 EQUIVALENTS of O, 1 mole of N contains 3 equivalents of N. THUS at NTP, 1 equivalent of H occupies 11.2 litres, 1 equivalent of O occupies `(11.2)/( 2) = 5.6` litres, 1 equivalent of N occupies `(11.2)/( 3) = 3.73` litres. |
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| 28. |
(v) MnO_(4)^(2-) to MnO_(4)^(2-)+MnO_(2) . |
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Answer» Solution :`underset(+6)(MnO_(4)^(2-))to underset(+7)(MnO_(4)^(-))+e^(-)` (Oxidation ) …………(1) `underset(+6)(MnO_(4)^(2-)+2e^(-))to underset(+4)(MnO_(2)) ` (Reduction) …………(2) MULTIPLY equation (1) by (2) `2MnO_(4)^(2-) to MnO_(4)^(-)+2e^(-)` …………(3) Add equation (2) and (3) `3MnO_(4)^(2-) to MnO_(2)+2MnO_(4)^(-)` Balance O atoms by adding `H_2O` on the side FALLING SHORT of oxygen atoms `3MnO_(4)^(2-)to MnO_(2)+2MnO_(4)^(-)+2H_(2)O` Balance H atoms by adding `H^(+)` on the side falling short of hydrogen atoms `3MnO_(4)^(2-)+4H^(+)to MnO_(2)+2MnO_(4)^(-)+2H_(2)O`. |
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| 29. |
Which of one following is applicable is applicable for an adiabatic expansion of an ideal gas? |
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Answer» `DELTAE = 0` |
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| 30. |
What is photochemical smog? What are its effects? How can it be controlled? |
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Answer» Solution :It is a kind of smog formed in warm, dry and sunny climate. It is formed when sunlight is absorbed by `SO_(2)` oxides of nitrogen and hydrocarbons. It act as an oxidising agent Effects of photochemical smog (i) It produces irritation in eyes and also in RESPIRATORY system. (ii) It can damage many MATERIALS such as metals, stones, building materials etc. (iii) `NO_2` present in photochemical smog gives it brown colour which reduces the VISIBILITY. (iv) It is harmful to fabrics, CROPS and ornamental plants: Control of photochemical smog (i) By using catalytic converters in automobiles. (ii) By spraying certain compounds into the atmosphere which generate firee radicals that can easily combine with the free radicals that initiates the reaction forming toxic compounds of photochemical smog (iii) Certain plants such as Pinus, Juniparus, Pyrus could be also helptul in this matter |
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| 31. |
Which of the following rae state functions? (a) Height of a hill (b) Distance travelled in climbing the hill (c ) Energy change in climbing the hill |
| Answer» SOLUTION :ENERGY CONSUMED in CLIMBING the HILL. | |
| 32. |
Which of the following is the most powerful oxidizing agent? |
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Answer» `F_(2)`<BR>`Cl_(2)` |
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| 33. |
Which one of the following is used as a metal cleaning solvent? |
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Answer» Isopropylidene CHLORIDE |
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| 34. |
Writethe electronicconfigurationof gadloniumwith Z=64 andpredict thesum of thespins ofunpairedelectrons. |
| Answer» Solution :The electronicconfigurationof Eu (Z= 63 )in accordance withaufbau principleis `= [Xe]^(54)6s^(2)4f^(7)5D^(10)` . Thenextelectron (i.e.,64 th )as EXPECTED doesnot goto 4f- subshellbut goesto 5- subshell due togreaterstability of theexactly half- filled4f- subshell. THUS ,the electronicconfigurationof gadlonium(Z= 64 ) =`[Xe ] 6s^(2)4f^(7)4d^(1)` . Althoughherethe lastelectron goesto 5d-orbital , still itis not calledd- blockelement butis calledf-blockelement sincethe inner4f- subshellis stillnot fullyfilled.NowGd (Z=64)has eight half - filledorbitalsi.e.,seven4f andone 5d therefore the sum of thespinsof unpaired electron `= 8 xx (1)/(2)=4` | |
| 35. |
Which of the following is not true ? |
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Answer» ORDINARY WATER is electrolysed more RAPIDLY than `D_(2)O`. |
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| 36. |
Which is a sweet-smelling liquid? |
| Answer» Solution :`CH_(3)I` | |
| 37. |
Which of the following compounds on decarboxylation with soda-lime will give toluene ? |
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Answer» Phenylacetic ACID |
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| 38. |
Write line formula and dash formula of following condensed formula. (i) CH_(2)OH CHOH CH_(2)OH (ii) CH_(3) CH_(2) CHOH CH_(2) CH_(2)OH (iii) CH_(3)CO CH_(2) CH_(2) CH (CH_(3))_(2) (iv) H_(2)NCH_(2) COOH |
Answer» SOLUTION :
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| 39. |
Write redox couples involved in the reaction (i)to (iv) given in question 34 |
| Answer» SOLUTION :(i) `CU^(2+)//Cu` and `ZN^(2+)//Zn ,(ii) Mg^(2+)//Mg` and `Fe^(2+)//Fe , (iii) Br_(2)//Br^(-)` and `CI_(2)//CI^(-) , (iv) Fe^(2+) //Fe` and `CD^(2+)//Cd` | |
| 40. |
Which substanceis known as Inorganic benzene ? |
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Answer» Borazine |
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| 41. |
What is the de Broglie length of an electron,which is accelerated from the rest,through a potential difference of 100v? |
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Answer» Solution :Potential difference =b=100v Potential energy=eV=`1.609xx10^(-19)cxx100` `1/2mv^(2)=1.609xx10^(-19)XX100` `1/2mv^(2)=1.609xx10^(17)J` `v^(2)=(2xx1.609xx10^(-10))/(m)` m=mass of elctron`=9.1xx10^(-31)KG` `:.v^(2)=(2xx1.609xx10^(17))/(9.1xx10^(-31))` `:.v=SQRT(2xx1.609xx10^(-17))/(9.1xx10^(31))`=`sqrt(2xx1.609xx10^(-17)xx10^(31)/(9.1)` `v=sqrt(3.218xx10^(14)/(9.1)` `v=5.93xx10^(6)m/s` `gamma=h/(MV) Where h=6.62xx10^(-34)JS` `=(6.62xx10^(-34))/(9.1xx10^(-31)xx5.93xx10^(6))` `1.2xx10^(-10)m` `gamma=1.2A` |
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| 42. |
When 2.4g of carbon reacted with X g of oxygen to form CO and CO_2, 50.4 kJ of heat was released and no reactant is left over. Standard heats of formation of carbon monoxide and carbondioxide are -110.5 kJ mol^(-1) and -393.5 kJ mol^(-1) respectively. Calculate X. |
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Answer» |
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| 43. |
The type of bond formed by CO with haemoglobin of blood is |
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Answer» Covalent |
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| 44. |
Which of the following carbocation will be most stable? |
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Answer» `PH_3C-` |
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| 45. |
Write balanced chemical equation for each of the following chemical reactions. heating calcium carbonate |
| Answer» Solution :`CaCO_(3)OVERSET(1070-1270 K)rarr CaO+CO_(2)` | |
| 46. |
Which element of group 13 forms amphotric hydroxide ? |
| Answer» SOLUTION :Both AL and GA FORM amphoterichydroxides. | |
| 47. |
Which of the following violates the Pauli exclusion principle :- |
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Answer» `uarrdarruarrdarr` |
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| 48. |
When potassium cyanate is heated, it gives |
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Answer» UREA |
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| 49. |
When photons of energy 4.25 eV strike the surface of a metal A, the ejected photoelectronshave maximum kinetic energy, T_(A) (expressed in eV) and de Broglie wavelength lambda_(A). The mximum kinetic energy of photoelectrons liberated from another metal B by photons of energy 4.20 eV is T_(B) = T_(A) - 1.50 eV. If the de Broglie wavelength of these photoelectrons is lambda_(B) = 2 lambda_(A), then which is not correct : |
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Answer» The WORK FUNCTION of A is 2.25 EV |
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| 50. |
Two samples of lead oxide were separately reduced to metallic lead by heating in a current of hydrogen. The weight of lead from one oxide was half the weight of lead obtained from the other oxide. The data illustrates |
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Answer» law of RECIPROCAL proportions |
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