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. |
In Hofmann bromamide reation, the carbonyl group is lost as______ |
| Answer» SOLUTION :CARBONATE ION `(CO_(3)^(2-))` | |
| 2. |
In Goldschmidt aluminothermic process, thermite contains |
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Answer» 3 PARTS of `Al_(2)O_(3) and 4 `parts of AL |
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| 3. |
In Hofmann's hypobromidereaction |
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Answer» Thealkylgroupin amide MIGRATE to oxygenatom |
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| 4. |
In Hofmann bromamide degradation reaction R-overset(O)overset("||")C-NH_(2)+KOH+Br_(2)rarr intermediates are: |
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Answer» `RCONHBr` |
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| 5. |
In Hoffmann Bromamide reaction which substance is treated with Br_(2)" and "NaOH to obtain amine ? |
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Answer» Isonitrile |
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| 6. |
In Hoffinann bromamide reaction, the reactive intermediate involved is a |
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Answer» CARBOCATION |
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| 7. |
In HO-overset(O)overset(||)S-OH the oxidation states of S are |
| Answer» ANSWER :A | |
| 8. |
In hexagonal systems of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism.Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them.A space-fitting model of this structure, called hexagonal closed-packed (HCP), is constitution of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible Three spheres are then placed over the first layer so that they touch each other and represent the second layer.Each one of these three spheres touches three spheres of the bottom layer.Finally, the second layer is covered with third layer that is identical to the bottom layer in relative position.Assume radius of even sphere to be 'r'. In hcp lattice, if a plane is drawn parallel to layers A and B at a distance c/8 above the layer B, it passes through centres of x tetrahedral and y octahedral voids.A plane parallel to layer A at a distance c/8 just below it passes through centres of p tetrahedral and q octahedral voids.Find (x+y+p+q) c is the cell parameter of hcp lattice, the vertical edge length. |
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Answer» 10 |
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| 9. |
In hexagonal systems of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism.Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them.A space-fitting model of this structure, called hexagonal closed-packed (HCP), is constitution of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible Three spheres are then placed over the first layer so that they touch each other and represent the second layer.Each one of these three spheres touches three spheres of the bottom layer.Finally, the second layer is covered with third layer that is identical to the bottom layer in relative position.Assume radius of even sphere to be 'r'. The volume of this HCP unit cell is : |
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Answer» `12sqrt2 r^3` BASE area`=6xxsqrt3/4(2r)^2` Volume of the hexagon=Area of base x Height `=6.sqrt2/3 a^2xxc=24sqrt2.r` |
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| 10. |
In hexagonal systems of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism. Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them. A space-filling model of this structure, called hexagonal close-packed (hcp), is constitued of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible. Three spheres are then placed over the first layer so that they touch each other and represent the second layer. Each one of these three spheres touched three spheres of the bottom layer. Finally, the second layer is convered with a third layer that is identical to the bottom layer in relative position. Assume radius of every sphere to be 'r'. The volume of this hcp unit cell is |
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Answer» `24 SQRT(2)r^(3)` |
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| 11. |
In hexagonalprimitiveunit cell, the Corneris sharedby: |
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Answer» 4 UNIT cells |
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| 12. |
In hexacyanomanganate (II) ion the Mn atom assumes Id^2sp^3 hybrid state. The number of unpaired electrons in the complex is: |
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Answer» 1 |
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| 13. |
In hexacyanomanganate (II) ion the Mn atom assumes d^2sp^3 hybrid state. The number of unpaired electrons in the complex is |
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Answer» 1 |
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| 14. |
In hexacyanomanganate (II) ion the Mn atom assumes a^2sp^3-hybrid states. The number of unpaired electrons in the complex is |
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Answer» 1 |
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| 15. |
In heterogeneous catalytic reactions involving solid catalyst and gaseous reactants, the catalysts, most generally used are |
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Answer» METALS |
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| 16. |
In heterogeneous catalytic reactions, catalyst in the finely divided form possesses higher catalytic reactivity. This is because |
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Answer» SURFACE area of the finely DIVIDED CATALYST is large |
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| 17. |
In He^(o+) ion sample e^(-) is in ground state. If photon of energy 52.24 eV is given to the sample all the atom goes to higher energy state. It again falls back up to ground state. If it is not emitting any lines in Balmer series then what is the maximum possible number of spectral lines observed |
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Answer» |
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| 18. |
In HCP or CCP constituent particles occupy 74% of the available space. The remaining space (26%) in between the spheres remains unoccupied and is called interstitial voids or holes.Considering the close packing arrangement, each sphere in the second layer rests on the hollow space of the first layer, touching each other. The void created is called tetrahedral void. If R is the radius of the spheres in the close packed arrangement then,R (radius of tetrahedral void) = 0.225 R In a close packing arrangement, the interstitial void formed by the combination of two triangular voids of the first and second layer is called octahedral coid. Thus, double triangular void is surrounded by six spheres. The centre of these spheres on joining, forms octahedron. If R is the radius of the sphere. in a close packed arrangement then,R (radius of octahedral void = 0.414 R).If the anions (A) form hexagonal close packing and cations (C ) occupy only 2/3rd octahedral voids in it, then the general formula of the compound is |
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Answer» AB |
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| 19. |
In HCP or CCP constituent particles occupy 74% of the available space. The remaining space (26%) in between the spheres remains unoccupied and is called interstitial voids or holes.Considering the close packing arrangement, each sphere in the second layer rests on the hollow space of the first layer, touching each other. The void created is called tetrahedral void. If R is the radius of the spheres in the close packed arrangement then,R (radius of tetrahedral void) = 0.225 R In a close packing arrangement, the interstitial void formed by the combination of two triangular voids of the first and second layer is called octahedral coid. Thus, double triangular void is surrounded by six spheres. The centre of these spheres on joining, forms octahedron. If R is the radius of the sphere. in a close packed arrangement then,R (radius of octahedral void = 0.414 R).In Schottky defect |
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Answer» cations are missing from the lattice sites and OCCUPY the interstitial sites |
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| 20. |
In HCP or CCP constituent particles occupy 74% of the available space. The remaining space (26%) in between the spheres remains unoccupied and is called interstitial voids or holes.Considering the close packing arrangement, each sphere in the second layer rests on the hollow space of the first layer, touching each other. The void created is called tetrahedral void. If R is the radius of the spheres in the close packed arrangement then,R (radius of tetrahedral void) = 0.225 R In a close packing arrangement, the interstitial void formed by the combination of two triangular voids of the first and second layer is called octahedral coid. Thus, double triangular void is surrounded by six spheres. The centre of these spheres on joining, forms octahedron. If R is the radius of the sphere. in a close packed arrangement then,R (radius of octahedral void = 0.414 R).Mark the false statement : |
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Answer» CsCl CRYSTAL shows Schottky DEFECT |
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| 21. |
In HCP or CCP constituent particles occupy 74% of the available space. The remaining space (26%) in between the spheres remains unoccupied and is called interstitial voids or holes.Considering the close packing arrangement, each sphere in the second layer rests on the hollow space of the first layer, touching each other. The void created is called tetrahedral void. If R is the radius of the spheres in the close packed arrangement then,R (radius of tetrahedral void) = 0.225 R In a close packing arrangement, the interstitial void formed by the combination of two triangular voids of the first and second layer is called octahedral coid. Thus, double triangular void is surrounded by six spheres. The centre of these spheres on joining, forms octahedron. If R is the radius of the sphere. in a close packed arrangement then,R (radius of octahedral void = 0.414 R).In the spinel structure, oxide ions are cubic close packed whereas 1/8th of tetrahedral voids are occupied by A^(2+) cations and 1/2 of octahedral voids are occupied by B^(3+) cations. The general formula of the compound having spinel structure is |
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Answer» `A_(2)B_(2)O_(4)` |
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| 22. |
In HCP or CCP constituent particles occupy 74% of the available space. The remaining space (26%) in between the spheres remains unoccupied and is called interstitial voids or holes.Considering the close packing arrangement, each sphere in the second layer rests on the hollow space of the first layer, touching each other. The void created is called tetrahedral void. If R is the radius of the spheres in the close packed arrangement then,R (radius of tetrahedral void) = 0.225 R In a close packing arrangement, the interstitial void formed by the combination of two triangular voids of the first and second layer is called octahedral coid. Thus, double triangular void is surrounded by six spheres. The centre of these spheres on joining, forms octahedron. If R is the radius of the sphere. in a close packed arrangement then,R (radius of octahedral void = 0.414 R).In the figure given below, the site marked as S is a |
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Answer» tetrahedral VOID |
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| 23. |
In HCI molecule, expected value of dipole momentis 6.12 D but experimental value is 1.03 D. Then, the percentage ionic character will be |
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Answer» `16.13` |
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| 24. |
In hcp arrangement the coordination number is |
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Answer» 6 |
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| 25. |
In the HCOO^- the two carbon-oxygen bonds are found to be of equal length. What is the reason for it? |
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Answer» The anion is obtained by the removal of a PROTON from the acid MOLECULE |
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| 27. |
In halogentionof nitroalkane |
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Answer» all halogonare replacedby HALOGENES |
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| 28. |
In halogens, which of the following decreases from fluorine to iodine? |
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Answer» BOND length |
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| 29. |
In halogens, which of the following increases from iodine to fluorine? |
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Answer» BOND LENGTH |
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| 31. |
In haloarenes C-Cl bond has partial double bond character, which is due to |
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Answer» INDUCTIVE effect |
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| 32. |
In Hall's process, the ore is mixed with : |
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Answer» Coke |
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| 34. |
In Hall-Herold process, act as an anode. |
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Answer» CARBON blocks |
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| 35. |
In Hall and Heroult's process, products liberated at anode and cathode are _________. |
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Answer» OXYGEN and aliminium respectively |
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| 36. |
In hall and Heroult's process , the molten electrolyte is covered with the layer of powdered coke, which help to _________ |
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Answer» PREVENT oxidation |
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| 37. |
In halides, halogen atom is attached to |
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Answer» `SP^(3)` hybridised carbon atom |
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| 40. |
In Haber's process of manufacture of ammonia, the Fe catalyst is poisoned by the pressure of ............. |
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Answer» Mo |
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| 42. |
In Haber's process, hydrogen is obtained by reacting methane with steam in presence of Nio as catalyst. The process is known as steam reforming. Why is it necessary to remove CO when ammonia is obtained by Haber's process ? |
| Answer» Solution :CO acts as a poison for the catalyst in the manufacture of AMMONIA by Haber.s PROCESS. Hence, it is NECESSARY to remove it. | |
| 43. |
In Haber's process, hydrogen is obtained by reacting methane with steam in presence of Nio as catalyst. The process is known as steam reforming. Why is it necessary to remove CO when ammonia is obtained by Haber's process? |
| Answer» Solution :It is necessary to REMOVE CO while obtaining ammonia from Heber PROCESS because, produced CO gas EFFECTS on the reactivity of iron CATALYST. | |
| 44. |
In Haber's process for manufacture of ammonia which metals acts as a promotor for iron ? |
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Answer» Cu |
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| 45. |
In Haber's process for NH_3 the temperature and pressure are respectively |
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Answer» `STP` |
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| 46. |
In haber process 30 litres of dihydrogen and 30 littres of dinitorgen were taken for reaction which yieided only 50% of the expected product. What will be the composition of gaseous mixture under these condition in the end |
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Answer» 20 litres ammonia, 25 litres NITROGEN, 15 litres hydrogen `{:(30,30,0),(30-x,30-3x,2x):}` `{:(,N_(2)=30-5=25 litre),(,H_(2)=30-3xx5=15litre),(,NH_(3)=2xx5=10 litre):}` |
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| 47. |
In Haber process, 30 litres of dihydrogen and 30 litres of dinitrogen were taken for reaction which yielded only 50% of the expected product. What will be the composition of the gaseous mixture under the aforesaid condition in the end? |
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Answer» 20 litres `NH_3`, 25 litres `N_2`, 20 litres `H_2` Thus, `N_(2)` is the limiting reacant. 10 L `N_(2)` will react with 30 L `H_(2)` to form 20 L `NH_(3)`. As actual yield is 50% of the EXPECTED value, `NH_(3)` formed = 10 L, `N_(2)` reacted = 5L, `H_(2)` reacted = 15 L `THEREFORE` Mixture will contain 10 L `NH_(3), 25 L N_(2), 15 L H_(2)` |
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| 48. |
In Haber process, 30 litres of dihydrogen and 30 litres of dinitrogen were taken for reaction which yielded only 50% of the expected product. What will be the compositon of the gaseous mixture under the aforesaid condition in the end? |
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Answer» 20 litres `NH_(3)`, 25 litres `N_(2)`, 20 litres `H_(2)` 1 L of `N_(2)` reacts with 3 L of `H_(2)` to form 2 L of `NH_(3)`. Thus, `N_(2)` is the limiting reactant. 10 L `N_(2)` will REACT with 30 L `H_(2)` to form 20 L `NH_(3).` As actual yield is `50%` of hte expected value, `NH_(3)`formed = 10 L, `N_(2)` REACTED = 5 L, `H_(2)` reacted = 15 L `therefore" Mixture will contain 10 L NH"_(3),25 L N_2),` `15L H_(2)`. |
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| 49. |
In H_(3)PO_(4), which of the following is true |
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Answer» `K_(a)=K_(a_(1))xxK_(a_(2))xxK_(a_(3))` `h_(2)PO_(4)^(-)hArrH^(+)+HPO_(4)^(2-)K_(a_(2))=([H^(+)][HPO_(4)^(-2)])/([H_(2)PO_(4)^(-)])""...(ii)` `HPO_(4)^(2-)hArrH^(+)+PO_(4)^(3-)K_(a_(3))=([H^(+)][HPO_(4)^(2-)])/([HPO_(4)^(2-)])""...(iii)` `H_(3)PO_(4)hArr3H^(+)+P_(4)^(3-)K_(a)=([H^(+)]^(3)[PO_(4)^(3-)])/([H_(3)PO_(4)])""...(iv)` Multiplying (i),(ii), (ii) and equate with (iv) `K_(a)=K_(AQ)xxK_(a_(2))xxK_(a_(3)),therefore(a)` is correct `1^(st)` acid dissociation constant is highest because dissociation is maximum in FIRST step, less in `2^(nd)` step and MINIMUM in `3^(rd)` step because it is difficult for a negatively changed ion tolose `H_(+)` ion. `K_(a_(1))gtK_(a_(2))gtK_(a_(3)), therefore(c)` is correct, (b) and (d) are ruled out. |
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| 50. |
In H_(3)PO_(3) molecule |
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Answer» P - atom is SURROUNDED by THREE - OH groups |
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