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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. |
One faraday of current was passed through the electrolytic cells placed in series containing solutions of Ag^(+), Ni^(++) and Cr^(++) respectively. The amounts of Ag (at wt. = 108), Ni (at. wt. = 59) and Gr (at. wt. = 52) deposited will be |
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Answer» Ag-108g, NI - 29.5 G, CR - 17.4 g |
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| 2. |
One Faraday of electricity is passed separately through one litre of one molar aqueous solutions of(i) AgNO_3 (ii) SnCl_4 and (iii) CuSO_4.The number of moles of Ag, Sn and Cu deposited at cathode are respectively |
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Answer» 1.0, 0.25, 0.5 |
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| 3. |
One faraday of electricity deposits one mol of Na from the molten salt but (1)/(3) mol of Al from an aluminium salt. Why? |
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Answer» Solution :The reactions at cathode for the deposit of Na and AL are `Na^(+)+e^(-)toNa and Al^(3+)+3e^(-)toAl` Thus, 1 FARADAY DEPOSITS 1 MOL of Na whereas 3 faradays are required for DEPOSITING one mol of Al. |
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| 4. |
One Faraday is equal to |
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Answer» `96.5c MOL^(-1)` |
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| 5. |
One Faraday charge was passed through the electrolytic cell placed in series containing solutionsof Ag^(+), Ni^(2+) and Cr^(3+). Then Ag, Ni and Cr deposited will be (Atomic masses , Ag= 108, Ni = 59 and Cr = 52) |
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Answer» |
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| 6. |
One faraday cantains the charge |
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Answer» 95000 C |
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| 7. |
One ecologically important equilibrium is that between carbonate and hydrogen carbonate ions in natural water. This standard Gibb's energies of formation of CO_(3)^(-2)(aq) and HCO_(3)^(Theta)(aq) are -527.8 kJ mol^(-1) and -586.8 kJ mol^(-1) respectively. For water, 2H_(2)O(l) +2e^(Theta) rarr H_(2)(g) +2OH^(Theta)(aq) , E_(RP)^(Theta) =- 0.83 V 2H_(2)O rarr O_(2) +4H^(+) +4e^(Theta), E_(OX)^(Theta) = - 1.23V The value of pK_(a) for HCO_(3)^(Theta) (aq) is (approx): |
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Answer» `9.3` |
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| 8. |
One electron volt is: |
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Answer» `1.6xx10^(-19)` ERG |
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| 9. |
One ecologically important equilibrium is that between carbonate and hydrogen carbonate ions in natural water. This standard Gibb's energies of formation of CO_(3)^(-2)(aq) and HCO_(3)^(Theta)(aq) are -527.8 kJ mol^(-1) and -586.8 kJ mol^(-1) respectively. For water, 2H_(2)O(l) +2e^(Theta) rarr H_(2)(g) +2OH^(Theta)(aq) , E_(RP)^(Theta) =- 0.83 V 2H_(2)O rarr O_(2) +4H^(+) +4e^(Theta), E_(OX)^(Theta) = - 1.23V What is the standard potential Couple of HCO_(3)^(-)//CO_(3)^(-2),H_(2). |
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Answer» `-0.305` VOLTS |
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| 10. |
One ecologically important equilibrium is that between carbonate and hydrogen carbonate ions in natural water. This standard Gibb's energies of formation of CO_(3)^(-2)(aq) and HCO_(3)^(Theta)(aq) are -527.8 kJ mol^(-1) and -586.8 kJ mol^(-1) respectively. For water, 2H_(2)O(l) +2e^(Theta) rarr H_(2)(g) +2OH^(Theta)(aq) , E_(RP)^(Theta) =- 0.83 V 2H_(2)O rarr O_(2) +4H^(+) +4e^(Theta), E_(OX)^(Theta) = - 1.23V Calculate the potential of a cell of pH = 7 in which the cell reaction is- Na_(2)CO_(3)(aq) +H_(2)O(l) rarr NaHCO_(3)(aq).+NaOH(aq) |
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Answer» `-0.22` VOLT |
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| 11. |
One dm^(3) solution containing 10^(-5) moles each of Cl^(-) ions and CrO_(4)^(2-) ions is treated with 10^(-4) moles of silver nitrate. Which one of the following observation is made. [K_(sp) Ag_(2)CrO_(4) = 4 xx 10^(-12)] [K_(sp)AgCl = 1 xx 10^(-10)] |
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Answer» Precipitation does not occur Ionic product of `Ag_(2)CrO_(4) = [10^(-8)][10^(-5)] = 10^(-13)` Ionic product of `AgCl gt K_(sp)` of AgCl So, precipitation will take place. Ionic product of `Ag_(2)CrO_(4) LT K_(sp)` of `Ag_(2)CrO_(4)` So, precipitation will not take place. |
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| 12. |
One dm^(3) solution containing 10^(-5) moles each of Cl^(-) ions and CrO_(4)^(2-) ions is treated with 10^(-4) moles of silver nitrate. Which one of the following observations is made ?[K_(sp)Ag_(2)CrO_(4)=4xx10^(-12)][K_(sp)AgCl=1xx10^(-10)] |
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Answer» PRECIPITATION does not OCCUR. Ionic product of `Ag_(2)Cr_(4)=[10^(-8)][10^(-5)]=10^(-13)` Ionic product of `AgClgtK_(sp)` of `AgCl` So, precipitation will take place. Ionic product of `Ag_(2)CrO_(4)ltK_(sp)` of `Ag_(2)CrO_(4)` So, precipitation will not take place. |
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| 13. |
One desires to prepare a positively charged sol of silver iodine . This can be achieved by |
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Answer» adding small amount of `AgNO_(3)` SOLUTION to KI solution in slight excess |
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| 14. |
One day, the chemistry teacher discussed the importance of alkaloids in our life. He told that alkaloids are a group of naturally occurring complex nitrogen containing compounds which produce a great physiological occurring complex nitrogen containing compounds which produce a great physiological action when administered into the body. these are synthesized by plants to protect them from insects and fungi. these are also toxic to human beings. although some of these are quite useful to us. Therefore, the teacher warned that these alkaloids should be taken, if needed, in small amounts because their higher doeses can prove fatal. After reading the above passage, answer the following questions, (i) Name the alkaloids present in tea leaves and what is its effect of human beings? (ii) Name the alkaloid present in opium and what are its uses? |
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Answer» Solution :(i) The alkaloid PRESENT in tea leaves is caffeince. It is a stimulant and activates the CENTRAL nervous system. Under its influence, one can work more EFFICIENTLY and for longer hours. (ii) the alkaloid present in opium is morphine. It is a powerful ANALGESIC and is given only when the PATIENT is in great pain. |
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| 15. |
One day, Sakshi's mother noticed that the water pipe line of her house was getting rusted. She did not want excavation of the pipe. She asked her dughter that as she was a student of science, she should suggest some method so that further rusting stops. Now, answer the following questions: (i) What values are expressed in the above paragraph? (ii) What do you think sakshi ust have suggested to her mother and why? |
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Answer» Solution :(i) Every MUST have some basic KNOWLEDGE of science and we should apply it to our day to day practival application. (ii) Sakshi must have SUGGESTED that magnesium BLOCK should be attached to water pipe line through an electric wire. It will act as anode and undergo oxidation in preference to iron and hence will protect iron-pipe from further RUSTING. |
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| 16. |
One day Nitin was discussing with hig class fellows the composition of oils and fats and their effect on our health. He suggested that fats and hydrogenated oils should not be used for cooking purposes but emphasized that only olive oil, canola oil, soyabean oil, sarson oil, groundnut oil, etc. should be used. After reading the above passage, answer the following questions. (i) What is the basic difference in the composition of oils and fats? (ii) What type of health problem is caused by consumption of saturated fats and how can this problem be checked by using olive oil, canola oil or any other oil? (iii) What values are displayed by Nitiin regarding use of oils instead of fats for cooking purposes? |
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Answer» Solution :(i) Vegetable OILS and ats both contain a mixture of esters of unsaturated fatty acids (mainly omega-`3^(**) and` omega`-6^(**)` fatty acids) and saturated fatty acids (palmitic acid, stearic acid, etc.) wit glycerol WHEREAS oils contain a much higher percentage of esters of omega-3 and omega-6 fatty acids, while FATS and hydrogenated oils contain a much higher percentage of esters of saturated fatty acids. (ii) Consumption of fats and hydrogenated oils increase the level of bad cholesterol (LDL-low density lipoprotein) in blood which sticks to the walls of the arteries and causes conorary heart disease. To check the occurrence of heart ATTACK, olive oil, canola oil, etc. which contain omega-3 and omega-6 fatty acids should be used for cooking purposes because they tend to decrease the level of LDL thereby increasing the level of HDL (high density lipoprotein) which PREVENTS the heart attacks. (iii) By suggesting that oils rather than fats be used for cooking purposes, nitin had displayed his concern about the general health of the people. |
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| 17. |
One coulomb of charge passes through a solution of AgNO_(3) and CuSO_(4) connected in series and the concentration of the two solutions is in the ratio 1:2. The ratio by weight of Ag and Cu deposited on Pt electrode is : |
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Answer» `107.9:63.54` `("Weight of AG deposited")/("Equivalent weight of Ag")=("Weight of Cu deposited")/("Equivalent weight of Cu")` `(W_(Ag))/(W_(cu))=(E_(Ag))/(E_(Cu))=(107 g)/((163.54)//2)=(107.9)/(31.77)` or `107.9:31.77` |
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| 18. |
One coulorb is the charge of |
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Answer» 1 mole of ELECTRONS |
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| 19. |
One coulomb of charge passes through solutions of AgNO_3 and CuSO_4. The ratio of the amountsof silver and copper deposited on platinum electrodes used for electrolysis is |
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Answer» `108 : 63.5 ` |
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| 20. |
One compound of the pair will react rapidly than the other. Identitify correcy order |
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Answer»
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| 21. |
One commercial system removes SO_(2) emmission from smoke at 95^(@)Cby the following set of reactions- SO_(2)(g)+ Cl_(2)(g) to SO_(2)Cl_(2)(g) SO_(2)Cl_(2) + 2H_(2)O to H_(2)SO_(4) + 2HCl H_(2)SO_(4) + Ca(OH)_(2) to CaSO_(4) + 2H_(2)O Assuming the process to be 95% efficient . How many moles of CaSO_(4) may be produced from 128 gSO_(2).[Ca=40,S-32,O-16] |
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Answer» 1.9 moles |
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| 22. |
One component of solution follows Raoult's law over the entrie range 0 le x_(1)le1. The second compenent must follow Raoult's law in the range when x_(2) is |
| Answer» Answer :D | |
| 23. |
One component of a solution follows Raoult's law over the entire range 0le x_(1) le1. The second component must follow Raoult's law in the range when x_(2) is |
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Answer» close to zero |
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| 24. |
One can obtained a silica garden if |
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Answer» crystales of COLOURED are added to a STRONG SOLUTION of sodium SILICATE |
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| 26. |
One can draw the map of a building on a glass plate by: |
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Answer» HI |
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| 27. |
One atomosphere is numerically equal to approximately : |
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Answer» `10^6` DYNE `CM^(-2)` |
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| 28. |
One atomic mass unit in kilogram is |
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Answer» `1//N_(A)` |
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| 29. |
One atom of an element X weighs 6.644 xx 10^(23) g. Calculate the number of gram-atoms in 40 kg of it. |
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Answer» SOLUTION :WT. of 1 mole of atoms of X = wt. of 1 atom x Av. const. `=6.44 xx 10^(-23) xx 6.022 xx 10^(23)` = 40 g Thus, the at. Wt. Of X=40 No. Of MOLES (or gram-atoms) of X `=("weight in g")/("at. Wt")` `=(40 xx 1000)/40 = 1000` |
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| 30. |
One atom of an element X weighs 6.664xx10^(-23) gm. The number of gram atoms in 40kg of it is: |
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Answer» 10 |
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| 31. |
One atom of……combines with one atom of bromine: |
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Answer» Ar |
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| 32. |
One atom of an element weighs 6.644xx10^(-23)g. Calcualte the number of gram atoms in 40kg of it. |
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Answer» Solution :Atomic mass of the element =Mass of one atom `xx0.62xx10^(23)` `=6.644xx10^(-23)xx6.02xx10^(23)=40G` 40g=40000g No. of gram ATOMS `=("Mass of the element in GRAMS")/("Atomic mass in grams")` `=(40000)/(40)=1000` |
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| 33. |
One analysis a certain compound was found to contain iodine and oxygen in the ratio of 254:80. the formula of the compound is: (At. Mass of 1=127,O=16) |
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Answer» IO |
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| 34. |
One among the langthanides ,Ce(III), can be easily oxidized to Ce(IV)(At. No. of Ce= 58) . Explain why ? Or Of the lanthanides, cerium (At. No. 58) forms a tetrapositive ion, Ce^94+) in aqueous solution. Why? |
| Answer» Solution :CE(III) having the configuration `4f^(1) 5D^(-) 6S^(0)` can EASILY lose an electron to acquire the configuration `4f^(0)` and form Ce(IV) . In fact , this is theonly `( + IV)` lanthanide which exists in solution. | |
| 35. |
One ampere of current is passed for 9650 sec. through molten AlCl_(3).What is the weight is grams of Al deposited at cathode ? |
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Answer» 0.9 |
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| 37. |
One a.m.u. stands for |
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Answer» an ATOM of CARBON `(C^12)` |
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| 38. |
One among the following complex ions will not show optical activity |
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Answer» `[Pt(Br)(Cl)(I)(NO_(2))(C_(5)H_(5)N)(NH_(3))]^(-)` |
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| 39. |
One among the following is an example of ferroelectric compound- |
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Answer» QUARTZ |
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| 40. |
One adding AgNO_(3) solution to a solution of [Pt(NH_(3))_(3)Cl_(3)]Cl, the percentage of total chloride ion precipitated is : |
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Answer» 100 |
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| 41. |
On which of the following properties does the coagulating power of lon depend- |
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Answer» the MAGNITUDE of the charge on the ION alone |
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| 42. |
On which of the following properties does the coagulating power of an ion depend ? |
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Answer» Both MAGNITUDE and SIGN of the CHARGE on the ION. |
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| 43. |
On which of the following properties does the coagulating power of an ion depend? |
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Answer» Both magnitude and sign of the CHARGE on the ION |
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| 44. |
On which of the following factors, the rate constant does not depend? |
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Answer» Temperature |
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| 45. |
On which basis homopolymer will named ? |
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Answer» Monomer UNIT |
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| 46. |
On what ground can you say that scandium (Z=21) is a transition element but zinc (Z=30) is not? |
| Answer» Solution :On the basis of INCOMPLETELY filled 3d-orbitals in case of SCANDIUM atom in its ground state `(3d^(1))`, it is regarded as a TRANSITION element. On the other HAND, zinc atom has completely filled d-orbitals `(3d^(10))` in its ground state as well as in its oxidised state, hence it is not regarded as a transition element. | |
| 47. |
On what ground can you say that scandium (Z= 21) is a transition element but zinc (Z= 30) is not ? |
| Answer» Solution :Sc `(Z= 21)` contains incompletely FILLED 3d orbital `( 3d^(1))` WHEREAS zinc contains compltely filled d-orbitals `( 3d^(10))` . Hence, by definition, scandium is a TRANSITIONELEMENT but zinc is not. | |
| 48. |
On what factors do the stability of the state of matter depends upon ? |
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Answer» SOLUTION : The stability of state of matter depends on two opposing factors : (i) Intermolecular force (II) Thermal energy Intermolecular forces tend to keep the molecules or atoms or ions closer while thermal energy tends to keep them apart by making them move faster. At sufficiently low temperature, the thermal energy is low and intermolecular forces bring them so close that they cling to one another and occupy fixed positions. These can still oscillate about their MEAN positions and substance EXISTS in solid state. |
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| 49. |
On what does the emf of a lead storage battery depend? |
| Answer» Solution :The emf of the cell DEPENDS on the concentration of `H_(2)SO_(4)`. As the cell reaction uses `SO_(4)^(2-)` ions, the concentration `H_(2)SO_(4)` decreases. When the cell potential FALLS to about 1.8V, the cell has to be recharged.. | |
| 50. |
On warming the iodine and aqueous sodium hydroxide a pale yellow precipitate and sodium salt of an acid having formula HOOC-CH_(2)-CH_(2)-COOH is formed. The structural formula of the compound could be: |
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Answer» `CH_(3)-CO-CH_(2)CH_(2)-CH_(3)` |
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