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. |
Iodine deficiency in diet causes: |
|
Answer» Beri-beri |
|
| 2. |
It is true that under certain coditions magnesium can reduce SiO_2 and silicon can reduce MgO. What are those conditions ? |
| Answer» Solution :Below 1623 K (or `1350^@C`), magnesium can reduce `SiO_2` but above 1623 K (or `1350^@C`), silicon can reduce `MgO`. This can be infrred from `DELTAG^@` vs T plots. | |
| 3. |
Iodine deficiency in diet causes : |
|
Answer» GOITRE |
|
| 4. |
It is used as food preservative |
|
Answer» SODIUM benzoate |
|
| 5. |
Iodine can exist in the oxidation states : |
|
Answer» `-1, +1, +3, +5` |
|
| 6. |
It is said Taj Mahal may be destroyed due to |
|
Answer» Flood in Yamuna river |
|
| 8. |
It is recommended that ammonia bottles be opened after cooling in ice for sometime. This is because |
|
Answer» It BRINGS tears to eyes |
|
| 9. |
It is safe to inject solutions isotonic with blood plasma intravenously. Explain. |
| Answer» SOLUTION :THISIS becausein this casenoosmosisoccurshenceneitherRBCswellnortheyshrink. | |
| 10. |
Iodine can be obtained from Nal solution by the action of: |
|
Answer» `CI_2` |
|
| 11. |
Iodine can be liberated as a result of : |
|
Answer» OXIDISING `Cl_(2)` by `I_(2)` |
|
| 12. |
It is practically difficult to calculate the equivalent conductivity of a weak electrolyte in aqueous solution. Comment. |
|
Answer» Solution :Equivalent conductance = `(k xx 1000)//"normality"`. The extent of dissociation of a weak is less. According the number of IONS FURNISHED in AQUEOUS solutions is less. The specific conductivity (k) of a weak electrolyte is in the order of `10^(-2) S m^(-1)` or less. Since k is less, it is difficult to calculate equivalent conductivity of a weak electrolyte. |
|
| 13. |
Iodine and sulphur dissolve in |
|
Answer» WATCH |
|
| 14. |
Iodine and hypo react to produce: |
|
Answer» `Na_2S` |
|
| 16. |
It is possible to obtain oxygen from air by fractional distiilation because |
|
Answer» oxygen is in a different group of the periodic table from nitrogen |
|
| 17. |
Iodination of alkane is made in presence of: |
| Answer» Answer :D | |
| 18. |
It ispossible to get pure benzoicacid from a sample containing impurities of naphthalene through the process of recrystallisation using benzene as a solvent? Give reason- |
| Answer» Solution :It is not possible to purify impure benzoic acid by recrystallisation using BENZENE as SOLVENT because both naphthanlene and benzoic acid are quite SOLUBLE in benzene. PURIFICATION is however possible if HOT water be used as the solvent because acid is soluble in hot water but naphthalene is not. | |
| 19. |
Iodides of alkanes can be conveniently prepared by treating the chloro or bromo-derivative with sodium iodide in acetone. The reaction is known as : |
|
Answer» FINKELSTEIN REACTION |
|
| 20. |
It is possible to obtain oxygen from air by fractional distillation because: |
|
Answer» Oxygen is in different group of PERIODIC table from nitrogen |
|
| 21. |
Iodimetric titrations are usually performed in neutralor mildly alkaline (pH = 8) or weakly acidic solutions. Which statement is not valid for this observation ? |
|
Answer» In strong alkaline SOLUTION, `I_2` disproportionate to `I^(-) and IO^(-)` |
|
| 22. |
It is often difficult to store radioactive isotopes of Kr and Xe. Suggest a method to store them. |
| Answer» Solution :During nuclear reactions, radioactive isotopes of Kr and Xe are produced which find large number of applications in medicine and INDUSTRY. For this purpose, these radioactive isotopes must be stored. A USEFUL METHOD to store them is to MAKE their hydrates by compressing them in WATER. The hydrates thus formed are stable and are kept at low temperatures and used as and when required. | |
| 23. |
Iodiantion of alkanes is carried out in the presence of : |
|
Answer» carbon TETRACHLORIDE |
|
| 24. |
Iodide of Million's base is: |
|
Answer» `K_2[HgI_4]` |
|
| 25. |
It is observed that only 0.39% of the original radioactive sample remains undecayed after eight hours.Hence: |
|
Answer» the half-life of that substance is 1 hour `tau_(1//2) = (0.693 xx 8)/(2.303 xx 2.4089) -= 1 , tau_(1//2) = 1 , lambda = 0.693 = I_(n) 2 , tau = (1)/(lambda) = (1)/(0.693) = (1)/(I_(n) 2)` `(2.303 log 2) xx (1)/(2) = 2 .303 log ((10^(8))/(N_(t))) , (t)/(2) log 2 = log ((10^(8))/(N_(t))) log (2)^(t//2) = log "" (10^8)/(N_t) , (10^8)/(N_t) = sqrt2 implies N_t = (1)/(sqrt2) 10^8` |
|
| 26. |
Iodex contains |
|
Answer» METHYL acetate |
|
| 27. |
It is observed that H_(2) and He gases always show positive deviation from ideal behaviour i.e ., Zgtl. This is because |
|
Answer» the value of 'a' is very large due to HIGH ATTRACTIVE FORCES |
|
| 28. |
..................involves conversion of solar energy into chemical energy. |
| Answer» SOLUTION :PHOTOSYNTHESIS | |
| 29. |
Inverted sugar is |
|
Answer» OPTICALLY inactive form of sugar |
|
| 30. |
Invertase bring about the conversion of |
|
Answer» Starch of glucose |
|
| 31. |
It is not possible to prepare aryl cyanides from aryl halides. Why? |
| Answer» SOLUTION :ARYL HALIDES are LESS REACTIVE towards nucleophilic substitution. | |
| 32. |
Invert sugar is obtained by hydrolysis of ........and contains equimolar amounts of ..........and ................ |
| Answer» SOLUTION :SUCROSE , `D(+)-`GLUCOSE and `D(-)`-FRUCTOSE. | |
| 34. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different ortho//para directing group at the 1 and 4 positions, the position of further substitution is not immediately clear. Sometimes steric effects determine the outcome. In other cases, electronic factors determine the outcome, and further reaction will be at the position activated by the more strongly activating group. Some substituens are so strongly activating that no catalyst is needed, and it is often diffcult to stop substitution after mono substituion. Mild condition are needed to restrict the reaction to mono-substitution. It is possible to reduce the activity such groups by side chain reaction so that the reaction can be stopped use can sometimes be made of removable blocking groups on the ring. Which of the following side reaction//s can be used to reduce the activity of strongly activating groups like -OH ? |
|
Answer» benzcylation |
|
| 35. |
Invert sugar is mixture of |
|
Answer» GLUCOSE and FRUCTOSE |
|
| 36. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different ortho//para directing group at the 1 and 4 positions, the position of further substitution is not immediately clear. Sometimes steric effects determine the outcome. In other cases, electronic factors determine the outcome, and further reaction will be at the position activated by the more strongly activating group. Some substituens are so strongly activating that no catalyst is needed, and it is often diffcult to stop substitution after mono substituion. Mild condition are needed to restrict the reaction to mono-substitution. It is possible to reduce the activity such groups by side chain reaction so that the reaction can be stopped use can sometimes be made of removable blocking groups on the ring. Which of the following is the correct major product ? |
|
Answer»
|
|
| 37. |
Invert sugaris a mixture of equal amount of ……….. . |
|
Answer» LACTOSE + MALTOSE |
|
| 38. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different ortho//para directing group at the 1 and 4 positions, the position of further substitution is not immediately clear. Sometimes steric effects determine the outcome. In other cases, electronic factors determine the outcome, and further reaction will be at the position activated by the more strongly activating group. Some substituens are so strongly activating that no catalyst is needed, and it is often diffcult to stop substitution after mono substituion. Mild condition are needed to restrict the reaction to mono-substitution. It is possible to reduce the activity such groups by side chain reaction so that the reaction can be stopped use can sometimes be made of removable blocking groups on the ring. Which of the following synthesis could be done in the ring step ? |
|
Answer»
|
|
| 39. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different group ortho/ para di- recting group at the 1 and 4 positions, the position of further substitution is not immediately clear. Which of following is the incorrect major product ? |
|
Answer»
|
|
| 40. |
Invert sugar is : |
|
Answer» Sucrose |
|
| 41. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different group ortho/ para di- recting group at the 1 and 4 positions, the position of further substitution is not immediately clear. Which of the following synthesis could be done in the single step ? |
|
Answer»
|
|
| 42. |
It is not advised to sleep in a closed room with a coke fire buring inside on a cold day because of the harmful effects of |
|
Answer» CO |
|
| 44. |
Itisnecessaryto use…………….In theiodinationof alkane . |
|
Answer» ALCOHOL |
|
| 45. |
Invert , maltase , zymase ,maltose,lactose . |
| Answer» Solution :MALTOSE. It is a CARBOHYDRATES WHEREAS OTHERS are enzymes. | |
| 46. |
It is necessary to usea silentelectricdischangein thepreparationof ozonefromdioxygen - why ? |
| Answer» SOLUTION :A silverelectricdischange PRODUCES lessheat, preventingdecomposition of `O_(3)`BACK to` O_(2)`. | |
| 47. |
Inversion of sucrose refers to |
|
Answer» oxidation of SUCROSE |
|
| 48. |
It is not adviasable to: |
|
Answer» Stir SUGAR SOLUTION with a steel spoon |
|
| 49. |
Inversion of sucrose (C_(12)H_(22)O_(11)) is first-order reaction and is studied by measuring angle of rotation at different instants of time underset(d)underset("Sucrose")(C_(12)H_(22)O_(11))+H_(2)Ooverset(H^(+))rarrunderset(d)underset("Glucose")(C_(6)H_(12)O_(6))+underset(l)underset("Fructose")(C_(6)H_(12)O_(6)) If (r_(oo)-r_(0))=a and (r_(oo)-r_(t))=(a-x) (where r_(0),r_(t) and r_(oo)) are the angle of rotation at the start, at the time t and at the end of the reaction respectively, then there is 50% inversion when : |
|
Answer» `r_(0)=2r_(t)-r_(OO)` |
|