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. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method. Carius is the name of |
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Answer» A chemist |
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| 2. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method.In the quantitative estimation of phosphorous by using magnesia misture, the formula used is: |
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Answer» <P>PERCENTAGE of `P =62/222 xx (W xx 100)/(w)` |
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| 3. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method.Kjeldahl.s is the name of |
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Answer» A chemist |
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| 4. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method. Carius method is used for the quantitative estimation of: |
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Answer» C and H |
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| 5. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method.Dumas and Kjeldahl.s methods are used for quantative estimation of: |
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Answer» C and H |
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| 6. |
Quantitative estimation of C, H, and extra elements (e.g., N,S,P and halogens) is carried out by Liebig.s combustion, Carius, Dumas, and Kjeldahl.s method.Liebig.s combustion method is used for the quantitive estimation of: |
| Answer» SOLUTION :Lie big.s combustion method is USED for the quantitative estimation of C and H. | |
| 7. |
Quantitative analysis of calcium is carried out by ........ |
| Answer» SOLUTION :FLAME PHOTOMETRY | |
| 8. |
Quantitaivemeasurementof nitrogenin anorganiccompoundis doneby themethod_____. |
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Answer» BERTHELOT method |
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| 9. |
Qualitative analysis of calcium can be done by using ....... |
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Answer» Microscope |
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| 10. |
Q.12, Q.13 and Q.14 by appropriately matching the information given in the three columns of the following table. In which amongs the following product is formed by free radical mechanism? |
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Answer» <P>I) II) P) |
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| 11. |
Q.12, Q.13 and Q.14 by appropriately matching the information given in the three columns of the following table. In which amongs the following more than one products are not formed? |
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Answer» IV) iv) R) |
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| 12. |
Q.12, Q.13 and Q.14 by appropriately matching the information given in the three columns of the following table. Match the correct combination? |
| Answer» Solution :N//A | |
| 13. |
Q. The molecule C_(3)H_(4)O_(3) is sequential reaction is |
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Answer» `HO-CH=CH-COOH` |
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| 14. |
Q. The conversion of (D) to (F) involves |
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Answer» ELECTROPHILIC addition |
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| 16. |
Q. In the sequential reaction, if instead of CO_(2),(CH_(3))_(3)C-Br is used. Product will be |
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Answer» `HC-=HC` |
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| 18. |
Q. C_(3)H_(2)O_(2)underset(KMnO_(4))overset("Hot alkaline")toProduct. One of the products is |
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Answer» `underset(CHO)OVERSET(CHO)(|)` |
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| 19. |
Q. 'B' in the above passage is |
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Answer» `Cu-C-=C-CH_(2)CH_(2)CH_(2)CH_(3)` |
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| 20. |
Q and S can be |
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Answer» `NaCl,Na_(2)S_(2)O_(3)` |
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| 21. |
Pyrolusite, MnO_(2), is the main ore from which manganese is produced. The manganese content of the ore may be determined by reducing the MnO_(2) under acetic conditions to Mn^(2+) with the oxalate ion, C_(2)O_(4)^(2-), the oxalate ion being oxidised to carbon dioxide during the reaction. The analytical determination is carried out by adding a known excess volume of oxalate solution to a suspension of the pyrolusite and digesting the mixture on a hot water bath until all the MnO_(2) has been reduced. The excess, unreacted oxalate solution is then titrated with standardised potassium permanganate, KMnO_(4) solution after which the manganese content of the ore can be calculated. A student prepared a standard solution of sodium oxalate by weighing 3.2 g of the dry anhydrous salt, dissolving it in distilled water and making the solution up to 500 mL. 25 mL of the oxalate solution required 24.76 mL of KMnO_(4) solution. Role of KMnO_(4) in the given titration can be described as : |
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Answer» OXIDISING AGENT |
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| 22. |
Pyrolusite, MnO_(2), is the main ore from which manganese is produced. The manganese content of the ore may be determined by reducing the MnO_(2) under acetic conditions to Mn^(2+) with the oxalate ion, C_(2)O_(4)^(2-), the oxalate ion being oxidised to carbon dioxide during the reaction. The analytical determination is carried out by adding a known excess volume of oxalate solution to a suspension of the pyrolusite and digesting the mixture on a hot water bath until all the MnO_(2) has been reduced. The excess, unreacted oxalate solution is then titrated with standardised potassium permanganate, KMnO_(4) solution after which the manganese content of the ore can be calculated. A student prepared a standard solution of sodium oxalate by weighing 3.2 g of the dry anhydrous salt, dissolving it in distilled water and making the solution up to 500 mL. 25 mL of the oxalate solution required 24.76 mL of KMnO_(4) solution. What is the molarity of KMnO_(4) solution ? |
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Answer» 0.04776 |
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| 23. |
Pyrolysis of Methane and ethane respectively are |
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Answer» EXOTHERMIC & ENDOTHERMIC |
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| 24. |
Pyrolusite, MnO_(2), is the main ore from which manganese is produced. The manganese content of the ore may be determined by reducing the MnO_(2) under acetic conditions to Mn^(2+) with the oxalate ion, C_(2)O_(4)^(2-), the oxalate ion being oxidised to carbon dioxide during the reaction. The analytical determination is carried out by adding a known excess volume of oxalate solution to a suspension of the pyrolusite and digesting the mixture on a hot water bath until all the MnO_(2) has been reduced. The excess, unreacted oxalate solution is then titrated with standardised potassium permanganate, KMnO_(4) solution after which the manganese content of the ore can be calculated. A student prepared a standard solution of sodium oxalate by weighing 3.2 g of the dry anhydrous salt, dissolving it in distilled water and making the solution up to 500 mL. 25 mL of the oxalate solution required 24.76 mL of KMnO_(4) solution. How many moles of C_(2)O_(4)^(2-) ions will be oxidised by 1 mole MnO_(4)^(-) ? |
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Answer» `1//2` |
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| 25. |
Pyrolusite, MnO_(2), is the main ore from which manganese is produced. The manganese content of the ore may be determined by reducing the MnO_(2) under acetic conditions to Mn^(2+) with the oxalate ion, C_(2)O_(4)^(2-), the oxalate ion being oxidised to carbon dioxide during the reaction. The analytical determination is carried out by adding a known excess volume of oxalate solution to a suspension of the pyrolusite and digesting the mixture on a hot water bath until all the MnO_(2) has been reduced. The excess, unreacted oxalate solution is then titrated with standardised potassium permanganate, KMnO_(4) solution after which the manganese content of the ore can be calculated. A student prepared a standard solution of sodium oxalate by weighing 3.2 g of the dry anhydrous salt, dissolving it in distilled water and making the solution up to 500 mL. 25 mL of the oxalate solution required 24.76 mL of KMnO_(4) solution. Molarity of the sodium oxalate solution is .. |
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Answer» 0.04776 |
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| 26. |
Pyrolusite, MnO_(2), is the main ore from which manganese is produced. The manganese content of the ore may be determined by reducing the MnO_(2) under acetic conditions to Mn^(2+) with the oxalate ion, C_(2)O_(4)^(2-), the oxalate ion being oxidised to carbon dioxide during the reaction. The analytical determination is carried out by adding a known excess volume of oxalate solution to a suspension of the pyrolusite and digesting the mixture on a hot water bath until all the MnO_(2) has been reduced. The excess, unreacted oxalate solution is then titrated with standardised potassium permanganate, KMnO_(4) solution after which the manganese content of the ore can be calculated. A student prepared a standard solution of sodium oxalate by weighing 3.2 g of the dry anhydrous salt, dissolving it in distilled water and making the solution up to 500 mL. 25 mL of the oxalate solution required 24.76 mL of KMnO_(4) solution. What is the equivalent mass of MnO_(2) in the present titration ? |
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Answer» `(M. W.)/(1)` |
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| 27. |
Pyridine like benzene, has six pi -electrons in delocalized pi -orbitals, but unlike benzene the orbitals will be deformed as electrons are more attracted towards the nitrogen atom because of its high electro negativity. This is reflected in the dipole of pyridine which has the negative end on N and the positive end on the nucleus. We can compare the respective properties of benzene, pyridine, pyrrole, furan and thiophene, which very frequently give aromatic electrophilic and nucleophilic substitution reactions in different positions. Which of the following compounds are aromatic. |
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Answer»
Is aromatic because planar, CONJUGATION, it follows Huckels rule(4M + 2)`PI` ELECTRONS. |
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| 28. |
Pyridine like benzene, has six pi -electrons in delocalized pi -orbitals, but unlike benzene the orbitals will be deformed as electrons are more attracted towards the nitrogen atom because of its high electro negativity. This is reflected in the dipole of pyridine which has the negative end on N and the positive end on the nucleus. We can compare the respective properties of benzene, pyridine, pyrrole, furan and thiophene, which very frequently give aromatic electrophilic and nucleophilic substitution reactions in different positions. Nitration, chlorination, bromination of pyridine is very difficult at normal conditions. Why? |
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Answer» High aromaticity of pyridine than benzene |
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| 29. |
(pV^(2)T^(2))/(n) What would be the SI unit for the quantity. |
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Answer» Solution :SI UNIT of `(PV^(2)T^(2))/(n)` `= ((Pa)(m^(3))^(2)(K)^(2))/(mol)` `= Pa XX m^(6)xx K^(2)xx mol^(-1)` where p = Pascal Pa V = Volume `= m^(3)` T = Absolute Temp. K n = mol. |
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| 30. |
Purpose of 'U' shaped perforated vessel in Nelson cell is mainly to prevent the reaction |
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Answer» `2NaOH+Cl_(2)RARRNACL+NaOCl+H_(2)O` |
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| 31. |
Purple of cassius is |
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Answer» COLLIDAL SOLUTION of GOLD |
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| 32. |
Purification of silicon element used in semiconductors is done by |
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Answer» Zone refining |
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| 33. |
Purest form of hydrogen is obtained by |
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Answer» PETROLEUM industry |
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| 34. |
Pure will can be obtained from sea water by |
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Answer» centrifugation |
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| 35. |
Pure water can be obtained from water by |
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Answer» cetrifugation |
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| 36. |
Pure substances which show conductivity similar to that of silicon and germanium are called __________Conductors |
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Answer» |
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| 37. |
Pure sodium chloride is not hydroscopic but common salt gets wet in rainy season ? Why so ? |
| Answer» Solution :PURE `NaCl` is not hygroscopic but table salt is impure NaCl containing impurities of `MgSO_(4) , CaSO_(4) , MgCl_(2) and CaCl_(2)` , all of these being hygroscopic absorb MOISTURE from air in rainy season . As a result , table salts gets wet . | |
| 38. |
Pure methane can be prepared by: |
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Answer» WURTZ reaction |
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| 39. |
Pure hydrogen is obtained by carrying electrolysis of |
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Answer» water CONTAINING `H_(2)SO_(4)` |
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| 40. |
Pure H_(2)O_(2)is not very stable and decomposes in the presence of light or on standing or heating overset((-1))(H_(2)O_(2l))+overset((2-)) (H_(2)O_((l)))+overset((0))(O_(2(g))) The oxidation state of oxygen in H_(2)O_(2) is 1 it is oxidistion state of zero in O_(2) and is reduced to an oxidation state of -2 in H_(2)O. Thus, this decomposition is an example of auto oxidation reduction reaction or disproportionation reaction. 30-volume, hydrogen peroxide means |
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Answer» 30% of `H_2O_2` by VOLUME |
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| 41. |
Pure H_(2)O_(2)is not very stable and decomposes in the presence of light or on standing or heating overset((-1))(H_(2)O_(2l))+overset((2-)) (H_(2)O_((l)))+overset((0))(O_(2(g))) The oxidation state of oxygen in H_(2)O_(2) is 1 it is oxidistion state of zero in O_(2) and is reduced to an oxidation state of -2 in H_(2)O. Thus, this decomposition is an example of auto oxidation reduction reaction or disproportionation reaction. The compound which gives H_(2)O_(2) on treatment with dilute acid is |
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Answer» `PbO_(2)` |
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| 42. |
Pure H_(2)O_(2)is not very stable and decomposes in the presence of light or on standing or heating overset((-1))(H_(2)O_(2l))+overset((2-)) (H_(2)O_((l)))+overset((0))(O_(2(g))) The oxidation state of oxygen in H_(2)O_(2) is 1 it is oxidistion state of zero in O_(2) and is reduced to an oxidation state of -2 in H_(2)O. Thus, this decomposition is an example of auto oxidation reduction reaction or disproportionation reaction. Pure H_(2)O is |
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Answer» Semi-Solid |
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| 43. |
Pure benzne freezes at 5.3^(@)C. A solution of 0.223g of phenyl acetic acid (C_(6)H_(5)CH_(2)COOH) in 4.4g of benzene (K_(f)=5.12 "K kg mol"^(-1)) freezes at 4.47^(@)C. From the observation one can conclude that : |
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Answer» phenyl ACETIC ACID exists as such in benzene |
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| 44. |
Pure ammonia is placed in a vessel at a temperature where its degree of dissociation (alpha) is appreciable. At equilibrium 2NH_(3) = N_(2) + 3H_(2) . |
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Answer» `K_p` does not change with PRESSURE |
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| 45. |
Psi^(2) = 0 represents |
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Answer» a node |
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| 46. |
Psi^2 (r , theta , phi) represents (for schrodinger wave mechanical model) |
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Answer» Amplitude of electron wave |
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| 47. |
Prussian blue colour is obtained by mixing together aqueous solution of Fe^(3+) salt with: |
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Answer» ferricyanide |
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| 48. |
Prove the relationship between C_(p) and C_(p) for an ideal gas. |
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Answer» Solution :At constant volume, the heat capacity, C is denoted by `C_v` and at constant pressure, this is denoted by `C_p`. At constant volume as `q_(V) = DELTA U = C_(v) Delta T` At constant pressure as `q_(p) = Delta H = C_(p) Delta T` The DIFFERENCE between `C_(p) and C_(v)` can be derived for an ideal gas as : For a mole of an ideal gas, `Delta H = Delta U + Delta (pV)` `= Delta U + Delta (RT)` `= Delta U+ R Delta T` `therefore Delta H = Delta U+ R Delta T ""...(1)` bn putting the values of `Delta H and Delta U` we have `C_(p) Delta T = C_(v) Delta T + R Delta T` `C_(p) = C_(v) + R` `C_(p) - C_(v) = R` |
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| 49. |
Prove that the pressure necessary to obtain 50% dissociation of PCl_(5)at 500 K is numerically equal to three times the value of the equilibrium constant, K_(p). |
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Answer» Solution :` {: (,PCl_(5),hArr,PCl_(3),+,Cl_(2),) , (" Intial moles",1,,0,,0,) , ("Moles at EQM".,1-0*5=0*5,,0*5,,0*5,"TOTAL " 1*5 "moles") :}` IfP isthe total requiredpressure, then ` p_(PCl_(5)) = (0*5)/(1*5) XX P=P/3, p_(PCl_(3)) = (0*5)/(1*5) xx P = P/3, p_(Cl_(2)) = (0*5)/(1*5) xx P= P/3` ` K_(p) = (p_(pCl_(3)) xx p_(cl_(2)))/(p_(PCl_(5)))= ((P//3)(P//3))/(P//3) = P/3 or P = 3 K_(P).` |
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| 50. |
Prove that valency is a periodic property. |
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Answer» SOLUTION :Variation in period: The number of valence electrons INCREASES from 1 to 8 on moving across a period. The valency of the elements with respect to hydrogen and CHLORINE increases from 1 to 4 and then decreases from 4 to zero. Variation in group: On moving down a group, the number of valence electrons remains same. All the elements in a group exhibit same valency. For example, all the elements of group 1 have valency equal to 1. Hence, valency is a periodic property. |
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