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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. |
If the solubility of Ca(OH)_(2) is sqrt3 , What is its solubility product ? |
| Answer» ANSWER :D | |
| 3. |
If the solubility of alum KAl(SO_4 )_2 is 2 xx 10^(-3) M, what its solubility product ? |
| Answer» Solution :`6.4 xx 10^(-11) mol^4 L^(-4)` | |
| 4. |
If the shortest wavelength of spectral line of H-atom in Lyman series is x. Then match the following for Li^(2+) |
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Answer» `Li^(2+) (Z=3) `, For Lyman SERIES `lambda_("max") , n_2 = 2 ` `lambda_("MIN") , n_2 = OO` |
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| 5. |
If the salt M_(2)X, QY_(2) and PZ_(3) have the same solubilities, their K_(sp) values are related as |
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Answer» `K_(sp) (M_(2)X) = K_(sp) (Q Y_(2)) lt K_(sp) (PZ_(3))` For `PZ_(3) , K_(sp) = S(3S)^(3)=27S^(4), ` i.e., much higher. Hence, (a) is the correct OPTION. |
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| 6. |
If the saturated solution of NH_4Cl is heated than what happen ? This solution is endothermic. |
| Answer» SOLUTION :`NH_4Cl_((s))` + WATER + heat = `NH_4Cl_((aq))`. This reaction is endothermic so according to Le-Chatelier.s principal reaction move in forward direction `NH_4Cl_((s))`become soluble and solubility INCREASES. | |
| 7. |
If the relative atomic mass of oxygen is 64 units, the molecular mass of CO becomes |
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Answer» 112 |
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| 8. |
If the recemic mixture of a carboxylic acid is treated with a dextro rotatory amino acid then the productsformed are |
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Answer» A PAIR of enantiomers |
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| 9. |
If the reaction is not occur in forward or reverse then ....... |
| Answer» Answer :A | |
| 10. |
If the reaction , A + B to C+D , is thermodynamically feasible, the time taken for half of reaction to occur will depend most precisely on |
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Answer» `DeltaS` |
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| 11. |
If the ratio of molar masses of two gases A and B is 1 : 4. What is the ratio of the average speeds ? |
| Answer» SOLUTION :`(r_1)/(r_2) = (p_1)/(p_2) SQRT((M_2)/(M_1)) and (C_1)/(C_2) = sqrt((M_2)/(M_1))` | |
| 12. |
If the ratio of enthalpy of formation of CO_2 and SO_2 is 4 : 3 and enthalpy of formation of CS_2 is 26 K.cal/mol. Find the enthalpy of formation of SO_(2(g)) on the basis of above reaction CS_(2(l)) + 3O_(2(g)) to CO_(2(g)) + 2SO_(2(g)) |
| Answer» SOLUTION :`-71.7` K.Cal/mol | |
| 13. |
If the radius of the first Bohr orbit is x, then de- Broglie wavelength of electron in 3rd orbit is nearly |
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Answer» 3x `:. mv ((a_(0) n^(2))/(Z)) = (nh)/(2pi)` For 3rd orbit, n = 3 and for hydrogen, Z = 1 `a_(0) = x` (Given, BOHR radius of H-atom) Hence, `mv(x xx 3^(2))/(1) = (3h)/(2pi) or mv = (h)/(6pi x)` `LAMDA = (h)/(mv) = (h)/(h//6pi x_ 6pi x` |
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| 14. |
If the radius ofMg^(2+) ions,Cs^(+) " ions" , S^(2-)ions andCl^(-)are0.65 Å, 1. 69 Å , 1.84 Å and 1.81 Å respectively , calculate the coordination number of the cation in the crystals of MgS, MgO and CsCl. |
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Answer» |
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| 15. |
If the radius of Mg^(2+) ion, Cs^+ ion, O^(2-) ion, S^(2-) ion and Cl^- ion are 0.65 Å, 1.69 Å, 1.40 Å, 1.84Å and 1.81 Å respectively, calculate the coordination numbers of the cations in the crystals of MgS, MgO and CsCl. |
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Answer» |
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| 16. |
If the radius of first Bohr orbit of H atom is x, then de Broglie wavelength of electron in 3^(rd) orbit is nearly |
| Answer» ANSWER :B | |
| 17. |
If the radius of first Bohr' orbit be alpha_(0), then the radius of the third orbit of hydrogen would be |
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Answer» `3alpha_(0)` |
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| 18. |
If the radius of Fe^(+ +) is 0.76A^@, the radius of Fe^(+ + +) may be |
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Answer» `0.64A^(o)` |
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| 19. |
If the radius of 3rd orbit of hydrogen atom is 'x' then the radius of 4th orbit of Li^(2+) ion would be: |
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Answer» `(27)/(16)X` `x=(9)/(1)xx0.529`Ã…. . .(i) `r_(4)(Li^(2+))=(16)/(3)xx0.529`Ã… . . . . (ii) Dividing eqns. (ii) by (i) `(r_(4)(Li^(2+)))/(x)=(16)/(27)` `r_(4)(Li^(2+))=(16xx x)/(27)`. |
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| 20. |
If the radius of an atom of an element is 75 pm and the lattice type is body-centred cubic, what is the edge of the unit cell ? |
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Answer» |
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| 21. |
If the radius of an atom of an element is 75 pm and the lattice type is body-centred cubic , what is the edge of the unit cell ? |
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Answer» |
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| 22. |
If the pressure and absolute temperature of 4 litres of SO_2 gas are doubled, the volume of this gas would be |
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Answer» 1 litre |
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| 23. |
If the pressure and absolute temperature of2 litres of CO_(2) are doubled, the volume of CO_(2)would become "_____________". |
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Answer» 2 litres |
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| 24. |
If the positions of Na^+ and Cl^- are interchanged in NaCl , having fcc arrangement of Cl^- ions then in the unit cell of NaCl |
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Answer» `NA^+` ions will decrease by 1 while `Cl^-` ions will INCREASE by 1 |
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| 25. |
If the position of the electron is measured within an accuracy of +- 0.002nm, calculate the uncertainty in the momentum of the electron. Suppose the momentum of the electron is h//(4pi xx 0.05)nm, is there any problem in defining this value? |
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Answer» Solution :`Delta x = 0.002 nm = 2 xx 10^(-3) nm = 2 xx 10^(-12) m` `Delta x xx Delta p = (h)/(4pi) " " :. Delta p = (h)/(4pi Delta x) = (6.626 xx 10^(-34) kg m^(2) s^(-1))/(4 xx 3.14 xx (2 xx 10^(-12) m)) = 2.638 xx 10^(-23) kg m s^(-1)` Actual momentum `= (h)/(4pi xx 0.05 nm) = (h)/(4pi xx 5 xx 10^(-10)m) = (6.626 xx 10^(-34) kg m^(2) s^(-1))/(4 xx 3.14 xx 5 xx 10^(-11) m)` it cannot be DEFINED as the actual magnitude of the momentum is smaller than the UNCERTAINTY. |
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| 26. |
If the positionof theelectronis measuredwithinan accuracyof +0.002nmcalculatetheuncertaintyin themomentumoftheelectronSupposethe momentumof the electronish// 4pi_(m) xx 0.05 nmis there any problemin definingthisvalue ? |
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Answer» <P> Solution :Uncertaintyin VELOCITY`(DELTA p ) `Accordingto Heisenberg `DELTAP = (h)/(4pi Delta x)` `=(6.626 xx 10^(34) js )/( (4xx 3.1428)(0.002 xx 10^(9) m))` `Delta p= 2.63854xx 10^(23) kgms^(-1)` Realmomentumof electron= `(h)/(4pi xx 0.05 nm)` In THISWAY realmomentum `1.054 xx 10^(24) ` is less thancalculatedvalue ofuncertainty`2.64 xx 10^(23)` So the momentumof electroncan notbedefineproperly. |
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| 27. |
If the Planck's constant h = 6.6 xx 10^(-34) Js, the de-Broglie wave length of a particle having momentum of 3.3 xx 10^(-24) kg.ms^(-1) will be |
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Answer» `2 xx 10^(-10)m` |
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| 28. |
If thephotonof thewavlength150pmstrikesan atomandone of tisinnerboundelectronisejectredout witha velocityof 1.5 xx 10^(7)ms^(-7)calculatethe energywith whichit isboundtothe nucleus . |
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Answer» Solution :Calculationof kineticenergy massof electron(m )= 9.1 `xx10^(31) KG` velocityof ejectedelectron( v) =1.5 `xx 10^(7) NM^(1)` `KE = (1)/(92) mv^(2)` `=(1)/(2)(9.1 xx 10^(31) kg(1.5 xx 10^(7)ms^(-1) )` `=10.2375xx 10^(17)` `1.02375 xx 10^(16) kgm^(2) s^(2)` Applyingenergy `=1.3252 xx 10^(15)J =13.252xx 10^(16) J` Energybondto thenucleus `(E_(0))`= minimumenergyrequiredfor ejectredelectron(e ) `E_(0)= (E- KE)` `=(13.252 xx 10^(16) J)(1.02375xx 10^(16)J)` `=(12.228 xx 10^(16)) + (1.602 xx 10^(19))` `=7.5483 xx 10^(3) eV` |
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| 29. |
If the moleucar wt of Na_(2)S_(2)O_(3) and I_(2) are M_(1) and M_(2) respectivly then what will be the equivalent wt of Na_(2)S_(2)O_(3) and I_(2) in the following reaction S_(2)O_(3)^(2-)+I_(2)rarrS_(4)O_(6)^(2-)+2I^(-) |
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Answer» `M_(1)M_(2)` Total INCREASES is O.N of S for two molecules of `Na_(2)S_(2)O_(3)=4xx2.5-2[2(+2)=2` `therefore` totoal INCREAE in O.N of S for two molecules of `Na_(2)S_(2)O_(3)` =1 `therefore` Eq mass =`M_(1)//1=M_(1)` Now `I_(2)rarr2I` total decrease is O.N PER molecule of `I_(2)=0-2(-1)=2` `therefore` Eq mass of `I_(2)=M_(2)//2` |
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| 30. |
If the molecular weight of H_(3)PO_(3) is M, its equivalent weight will be |
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Answer» M |
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| 31. |
If the molecules of SO_(2)effuse a distance of 150cm in a certain period of time, the distance travelled by the molecules of CH_(4)effusing in the same time is |
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Answer» `300 CM ` |
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| 32. |
If the mechanism is E1cB then the possible products will be : |
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Answer» |
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| 33. |
If the mean free path is ' lambda' at one atm pressure then its value at 5 atm pressure is |
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Answer» <P>`5 LAMBDA` |
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| 34. |
IF the mean velocity of molecules of a gas is 4.79 xx 10^(4) cm s^(-1), find the most probable velocity of the molecules under similar conditions. |
| Answer» SOLUTION :`4.25 xx 10^(4) CMS^(-1)` | |
| 35. |
If the mass percent of various elements of a compound' is known, its empirical formula can be calculated What is mass percent? Give its mathematical expression |
| Answer» SOLUTION :Mass PERCENTAGE of a component in a solution is the weight of that component-present in 100 G to the solution. Mass PER cent =`"Mass of the solute"/"Mass of the solution "XX100` | |
| 36. |
If the mass of proton is doubled and that of neutron is havled th emolecular weight of CO_(2)consisting only isoeletronic series? |
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Answer» <P>`N^(3-),O^(2-),CL^(-),NE` No, of protons =6+16=22 No, of neutrous =6+16=22 New total mass `=22xx2+(22)/(2)=55` INCREASES in mass =11 % increase `=(11)/(44)xx100=25%` |
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| 37. |
If the mass of one molecule of water is 18 amu, what is the mass of one mole of water molecules? |
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Answer» |
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| 38. |
If the mass defect of ""_(4)^(9)X is 0.099 a.m.u. , then binding energy per nucelon is (1 a.m.u, 931.5 MeV) |
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Answer» 10.25 MeV `E=0.099 XX 931.5` MeV E(per nucleon)`=(0.099xx931.5)/(9)` MeV (No. of NUCLEONS in `""_(4)^(9)X=9`) `=(99xx931.5)/(9xx1000)=10.2465` MeV |
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| 39. |
If the lowest energy X-rays have lambda = 3.055 xx 10^(-8)m, estimate the minimum difference in energy between two Bohr.s orbits such that an electronic transition would correspond to emission of an X-ray. Assuming that the electrons in other shells exert no influence, at what Z(minimum) would a transition from the second energy level to the first result in the emission of an X-ray ? |
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Answer» |
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| 40. |
If the kinetic energy of an electron is 4.55 xx 10^(-25)J, find its wavelength (Planck's cosntant, h = 6.625 xx 10^(-34) kgm^(2)s^(-1), m = 9.1 xx 10^(-31)kg). |
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Answer» Solution :`"KE of ELECTRON, "1//2mv^(2)=4.55xx10^(-25)J`. `"Mass of electron, m"=9.1xx10^(-31)KG` `V^(2)=(2xxKE)/(m)=(2xx4.55xx10^(-25)J)/(9.1xx10^(-31)kg)RARR v^(2)=10^(6)m^(2)s^(-2)` `"Velocity of electron, v"=SQRT(10^(6))=10^(3)ms^(-1)` `therefore"Wave length, "lambda=(6.625xx10^(-34)Lgm^(2)s^(-1))/(9.1xx10^(-31)kgxx10^(3)ms^(-1))` `therefore"Wave length of electron "=lambda=728nm.` |
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| 41. |
If the kinetic energy of a particle is doubled, by what factor the de Broglie wavelength of the particle increase or decrease ? |
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Answer» Solution :`lamda = (H)/(SQRT(2 E m))` where E = kinetic energy of the particle `:. (lamda_(1))/(lamda_(2)) = sqrt2 or lamda_(2) = (lamda_(1))/(sqrt2) = (1)/(1.414) lamda_(1) = 0.7 xx lamda_(1)` Hence, de Broglic wavelength will DECREASE to 0.7 of its original value |
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| 42. |
If the kinetic energy of sa particle is reduced to half .Eebroglie wave length becomes. |
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Answer» 2 times |
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| 43. |
If the kinetic energy in j, of CH_(4) (molar mass =16 g mol^(-1)) at T (K) is X, the kinetic energy in j , of O_(2) (molar mass = 32 g mol^(-1)) at the same temperature is |
| Answer» ANSWER :A | |
| 44. |
If the KCN and HCN are present in aqueous solution then write equation of equilibrium constant. |
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Answer» SOLUTION :`KCN to H^(+)+ CN^-` `HCN HARR H^(+) + CN^-` `Ka(HCN)=([H^+][CN^-])/([HCN])` Here , `[CN^-]` = (Addition of CONCENTRATION of `CN^-` of KCN and HCN) |
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| 45. |
If the lonisation potential (I.P.) of Na is 5.48 eV. The I.P. of K will be |
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Answer» 4.34 EV |
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| 46. |
If the ionic radii of M^(o+) and X^(ө)are about 135 pm, then expected values of metallic radii of M and X should be respectively |
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Answer» 65 and 230 pm |
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| 47. |
If the ionisation energy and electron affinity of an element are 275 and 86 Kcals "mol"^(-1) respectively, the electronegativity of that element on Mulliken scale is |
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Answer» 2.8 |
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| 48. |
If the ionic product of water (K_(w) ) is 1.96 xx 10^(-14) at 35^(circ)C what is its value at 10^(circ)C? |
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Answer» `1. 96 xx 10^(-14)` ` THEREFORE K w lt 10 ^(-14)rArr 2. 95 xx 10 ^(-15) ` |
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| 49. |
If the internal energy of 22g CO_2 at 273K is .U", internal energy of which of the following is "4U" at same T ? |
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Answer» `5.5 CO_2` |
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| 50. |
If the impurities present in an ore or the products obtained from them are basic, the refractory lining of the furnace should preferrably be |
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Answer» acidic |
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