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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. |
An azeotropic mixture of `HCl` and water hasA. 36 % HClB. 20.2 % HClC. 48 % HClD. 57 % HCl. |
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Answer» Correct Answer - B This azeotropic mixture of HCl `+ H_(2)O` boils at a constant temperature of `108.6^(@)C`. |
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| 2. |
In Kroll and `Icl` process of the production of titaninum, the inert gas used is:A. NeB. KrC. ArD. Xe. |
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Answer» Correct Answer - C Argon is used to ensure the absence of air |
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| 3. |
A gas which is used as anaesthetic in dental surgery isA. NOB. `N_(2)O`C. `NO_(2)`D. CO. |
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Answer» Correct Answer - B `N_(2)O` (laughing gas) is used as anaesthetic in dental surgery. |
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| 4. |
A student is asked to draw the college building on a piece of glass. He would use :A. Hydrochloric acidB. Hydrofluoric acidC. Hydrobromic acidD. Hydroiodic acid. |
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Answer» Correct Answer - B HF dissolves glass `SiO_(2) + 4HF rarr SiF_(4) + 2H_(2)O` `SiF_(4) + 2HF rarr H_(2)SiF_(6)` |
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| 5. |
Which of the following trihalides is not hydrolysedA. `NF_(3)`B. `PCl_(3)`C. `AsCl_(3)`D. `SbCl_(3)`. |
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Answer» Correct Answer - A `NF_(3)`, due to the non availability of d-orbitals. |
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| 6. |
Which of the following is a Pseudohalogen ?A. `C_(2)N_(2)`B. `Cl_(2)`C. `ICI`D. `ClF_(3)`. |
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Answer» Correct Answer - A Cyanogen `(CN)_(2)` or `C_(2)N_(2)` is a pseudohalogen because of resemblence in properties to the halogen. |
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| 7. |
The noble gas which form interstitial compound with metals isA. HeB. NeC. KrD. Xe. |
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Answer» Correct Answer - A Only He forms interstitial compounds with metals. |
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| 8. |
The only noble gas recovered from natural gas isA. KnB. RnC. ArD. He. |
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Answer» Correct Answer - D Helium is mostly recovered from natural gas which may contain upto 8% of He. |
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| 9. |
The noble gases found dissolved in spring water areA. HeB. NeC. XnD. Kr. |
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Answer» Correct Answer - A He produced by the decay of radioactive minerals (`alpha`-particles change into He atom by accepting two electrons) get dissolved) in spring water. |
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| 10. |
Which of the following acts as an acid in sulphuric acid ?A. `HNO_(3)`B. `H_(3)PO_(4)`C. WaterD. `HClO_(4)` |
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Answer» Correct Answer - D `HClO_(4)` acts as an acid in conc. `H_(2)SO_(4)` because it gives a proton to `H_(2)SO_(4)`. `HClO_(4) + H_(2)SO_(4) rarr ClO_(4)^(-) + [H_(3)SO_(4)]^(+)` `HNO_(3), H_(3)PO_(4)` and `H_(2)O` act as bases in conc. `H_(2)SO_(4)` |
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| 11. |
Halide of sulphur used in the vulcanisation of rubber isA. `SF_(4)`B. `SF_(6)`C. `S_(2)Cl_(2)`D. All the three. |
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Answer» Correct Answer - C `S_(2)Cl_(2)`, sulphur monochloride is used in the vulcanisation of rubber. |
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| 12. |
Which of the following two are isostructural ?A. `XeF_(2), IF_(2)`B. `NH_(3), BF_(3)`C. `CO_(3)^(2) ,SO_(3)^(2)`D. `PCl_(5), ICl_(5)`. |
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Answer» Correct Answer - A `XeF_(2)` is a linear molecule (Xe is `sp^(3)d^(2)` hybridised with three equitorial positions by lone pairs). `IF_(2)` is also a linear molecule as explained below. No of electron around I = 7 + 2 + 1 (due to -ve charge) = 10 There, I is `sp^(3)d^(2)` -hybridised. There are 3 lone pairs and 2 bond pairs. Thus, its structure is similar to `XeF_(2)`. |
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| 13. |
The noble gases heavier than air areA. ArB. HeC. NeD. Kr. |
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Answer» Correct Answer - A::D Out of the given four noble gases only Ar (At. Mass 39) and (Kr (At. Mass 84) are heavier than air. He (At. Mass 4) and Ne (At. Mass 20) are lighter than air. |
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| 14. |
Which of the following is used in flash tubes in photography ?A. NeB. KrC. ArD. Xe. |
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Answer» Correct Answer - B::D Xe and Kr are used in flash tubes for high speed photography. These have now completely replaced the old flash bulbs using Mg ribbon or Al powder which could only be used once. |
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| 15. |
Which of the following is used to stimulate the growth of plants ?A. HeB. NeC. ArD. Rn. |
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Answer» Correct Answer - B Neon. |
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| 16. |
Which gas is called super halogen?A. `F_(2)`B. `Cl_(2)`C. `Br_(2)`D. `I_(2)`. |
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Answer» Correct Answer - A `F_(2)` is known as superhalogen due to its high reactivity. |
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| 17. |
which of the following is called Mephitic air by Rutherford ?A. `N_(2)`B. `O_(2)`C. `NH_(3)`D. `H_(2)` |
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Answer» Correct Answer - A `N_(2)` was given the name mephitic air (meaning killer of life) by D. Rutherford. |
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| 18. |
Bleaching powder slowly loses its activity when it stand in air. This is due toA. Reaction with `CO_(2)` to evolve `Cl_(2)`B. Reaction with moisture to liberate `O_(2)`C. Loss of `CaCl_(2)`D. Formation of `Ca(OH)_(2)` |
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Answer» Correct Answer - A `CaOCl_(2) + CO_(2) rarr CaCO_(3) + Cl_(2)` because `Cl_(2)` is lost. |
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| 19. |
Which of the following is not a bleaching agent ?A. `Cl_(2)` (moist)B. `Br_(2)`C. `CaOCl_(2)`D. `NaClO`. |
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Answer» Correct Answer - B All the three except `Br_(2)` act as bleaching agent. |
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| 20. |
Euchorine isA. `Cl_(2) + CO_(2)`B. `ClO_(2) + Cl_(2)`C. `Cl_(2)O_(3) + Cl_(2)`D. `Cl_(2)O_(7)`. |
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Answer» Correct Answer - B Euchlorine is `ClO_(2) + Cl_(2)`. |
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| 21. |
Which of the following does not give borax bead test ?A. Cobalt saltB. Chromium saltC. Iron saltD. Zinc salt. |
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Answer» Correct Answer - D Borax bead test is for coloured salts only. Zinc salts are white so this is not given. |
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| 22. |
Which of the following is monoatomic?A. OxygenB. NeonC. FluorineD. Nitrogen. |
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Answer» Correct Answer - B All noble gases exist in monoatomic state. Maximum number of compounds of only Xe are known. |
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| 23. |
Which of the following gases is used in very low temperature thermometers ?A. `H_(2)`B. `He`C. Ne`D. `N_(2)`. |
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Answer» Correct Answer - B Helium (due to its very low b.p.) is used in low temperature thermometers. |
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| 24. |
The noble gases have closed-shell electronic cordigaration and are monatomic gases under normal condition .The low bolling points of the ligher noble gases aree due to the weak dispersion points of the ligher noble gases an due to the weak dispersion forces between the atoms and the alsence of other interalumic interactions. The direct reaction of xenon with flarine loads to a series of compounds with water oxidation number `+2, - 4 and +6, XeF_(4)` reactsviolenatly with water to give `XeO_(2)` .The compound of deduced axbibt nci strouchemistry and their goometries can be deduced considering the total number of electron puirs in the valence shell. Argon is used in arc welding because of itsA. low reactively with metalB. ability to lower the melting point of metalC. flamabilityD. high calorific value. |
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Answer» Correct Answer - A Argon is used in are welding to cause the atmosphere around without interaction with metal. |
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| 25. |
`XeF_(2)` is iso-structural withA. `SbCl_(3)`B. `BaCl_(2)`C. `TeF_(2)`D. `ICl_(2)^(-)`. |
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Answer» Correct Answer - D `BaCl_(2)` is ionic, `SbCl_(3)` (`sp^(3)`, one lone pair-pyramidal) while `XeF_(2)` (`sp^(3)d`, three lone pairs) and `ICl_(2)^(-)` (`sp^(3)` three lone pairs) both are linear and hence isostructural. |
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| 26. |
Brimstone is another name for:A. Lapis LazuliB. SodiumC. PhosphorusD. Sulphur. |
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Answer» Correct Answer - D Brimstone is another name for sulphur. |
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| 27. |
Which of the following statements about noble gases is false ?A. They are used to provide inert atmosphere in many chemical reactionsB. They are only sparingly soluble in waterC. They form diatomic moleculesD. Some of them are used to fill discharge tubes used for advertising signs. |
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Answer» Correct Answer - C Noble gases are always monoatomic. |
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| 28. |
Which of the following outer electronic configuration represents argon ?A. `ns^(2)`B. `ns^(2)np^(6)`C. `ns^(2)np^(5)`D. `ns^(2)np^(4)`. |
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Answer» Correct Answer - B Valence shell electronic configuration of noble gases is `ns^(2)np^(6)`. |
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| 29. |
……….. Is called white graphiteA. Boron nitrideB. BorazineC. Boric acidD. Boraxine. |
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Answer» Correct Answer - A BN has a structure similar to graphite (`sp^(2)` hybridisation at B and N), hence it is also called white graphite. |
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| 30. |
Which of the following elements from `p pi - d pi` bonding in its oxides ?A. LiB. PC. ND. B. |
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Answer» Correct Answer - B It is due to the availability of vacant d-orbitals in the valence shell of phosphorus. |
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| 31. |
The structure of `XeF_(6)` isA. Distorted octahedralB. PyramidalC. TetrahedralD. None of the above. |
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Answer» Correct Answer - A The structure of `XeF_(6)`, with six bond pairs and one lone pair is distorted octahedral. |
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| 32. |
Argon is usedA. to obtain low temperatureB. be high temperature weldingC. in high temperature for treatment of cancerD. in filling air ships. |
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Answer» Correct Answer - B Argon is used in producing inert atmosphere during welding and extraction of various metals. |
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| 33. |
Which of the following gases is used in very low temperature thermometers ?A. HeB. NeC. `H_(2)`D. `N_(2)`. |
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Answer» Correct Answer - A Helium. |
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| 34. |
Percentage of argon in air isA. nearly half as that of `CO_(2)`B. nearly double as that of `CO_(2)`C. nearly thirty times as that of `CO_(2)`D. None of these. |
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Answer» Correct Answer - C Percentage of argon in air is nearly 1 precent while percentage of `CO_(2)` in air is nearly 0.03 percent. Thus, argon is nearly thirty times more than `CO_(2)` in air. |
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| 35. |
percentage of argon in air is aboutA. `1 %`B. `2 %`C. `3 %`D. `4 %`. |
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Answer» Correct Answer - A Percentage of argon in air is nearly 1 %. |
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| 36. |
The oxalate of which of the following elements is component of most kidney stonesA. MgB. CaC. BaD. Na. |
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Answer» Correct Answer - B `Mg_(2)C_(3) + 4HOH rarr underset("Allylene")(C_(3)H_(4)) + 2Mg(OH)_(2)`. |
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| 37. |
Anhydrone, a drying agent isA. `HClO_(4)`B. Anhyd. Magnesium perchlorateC. Anhyd. Calcium perchlorateD. Potassium chlorate. |
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Answer» Correct Answer - B `Mg(ClO_(4))_(2)` anhydrous is known as Anhydrone and is used as a dessicant. |
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| 38. |
Percentage of silver in silver paint isA. 0.5B. 0.25C. 0.3177D. 0 |
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Answer» Correct Answer - D Actually a mixture of Al powder in Linseed oil is used as silver paint. It does not contain silver. |
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| 39. |
Welding of magnesium can be done in an atmosphere ofA. `O_(2)`B. `N_(2)`C. HeD. All. |
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Answer» Correct Answer - C He being an inert and non-inflammable gas. |
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| 40. |
Gradual addition of electronic shells in the noble gases causes a decrease in theirA. Ionization energyB. Atomic radiusC. Boiling pointD. Density. |
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Answer» Correct Answer - A Gradual addition of electronic shell in the Noble gases causes a decrease in their ionisation energy basically because of increase in atomic radius. |
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| 41. |
The gaseous mixture used by deep sea divers for respiration isA. `O_(2) + He`B. `O_(2) + Xe`C. `O_(2) + Ar`D. `O_(2) + N_(2)`. |
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Answer» Correct Answer - A A mixture of `O_(2)` and He is used for breathing by deep sea divers. |
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| 42. |
The gas which is used in air ships isA. NeB. HeC. ArD. Xe. |
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Answer» Correct Answer - B Due to non inflammable nature. |
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| 43. |
Of the following species, one which is nonexistent isA. `XeF_(4)`B. `XeF_(2)`C. `XeF_(5)`D. `XeF_(6)`. |
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Answer» Correct Answer - C Xenon show oxidation state of 0, + 2, + 4, + 6 and not + 5. |
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| 44. |
Which of the noble gas has highest polarizabilityA. HeB. ArC. KrD. Xe. |
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Answer» Correct Answer - D Xenon due to largest size. |
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| 45. |
The dielectric constant for `H_(2)O` at `18^(@)C` isA. 22B. 82C. 28D. 88 |
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Answer» Correct Answer - B Dielectric constant for `H_(2)O` is 82 at `18^(@)C` and for `NH_(3)` is 22. |
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| 46. |
Hydrogen has three isotopes, the number of possible diatomic molecules will beA. 3B. 6C. 9D. 12 |
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Answer» Correct Answer - B `._(1)H_(2)^(1), ._(1)H_(2)^(2), H^(1)H^(2), H^(1)H^(3), H^(2)H^(3)` |
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| 47. |
Saturated hydrides of silicon are calledA. SiliconesB. SilanesC. SilicatesD. None. |
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Answer» Correct Answer - B Silanes are compounds of silicon analogous to the alkanes, compounds of carbon. |
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| 48. |
Hydrazine reduces Fehling solution toA. CuOB. `Cu_(2)O`C. `Cu + O_(2)`D. `Cu(OH)_(2)`. |
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Answer» Correct Answer - B `underset("Hydrazine")(NH_(2)NH_(2)) + underset("solution")underset("From Fehling")(4Cu(OH)_(2))rarr underset(("red"))underset("Cuprous oxide")(2Cu_(2)O) + 6H_(2)O + N_(2)` |
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| 49. |
Sulphur heptoxide is an anhydride ofA. `H_(2)S_(2)O_(8)`B. `H_(2)S_(2)O_(7)`C. `H_(2)SO_(4)`D. `H_(2)SO_(5)`. |
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Answer» Correct Answer - A `S_(2)O_(7) + H_(2)O rarr underset("Persulphuric acid")(H_(2)S_(2)O_(8))` |
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| 50. |
Colloidal sulphur is obtained by the action of HNO onA. `H_(2)S`B. `HgS`C. `CaS_(2)O_(3)`D. CuS. |
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Answer» Correct Answer - A `H_(2)S + underset("From"HNO_(3))([O])rarrH_(2)O + underset("Colloidal")(S)` |
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