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. |
If 18g of glucose (C_(6)H_(12)O_(6)) is present in 1018 g of an aqueous solution of glucose, it is said to be |
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Answer» 1 MOLAL As it is present in (1018-18) = 1000 g WATER, the solution is 0.1 molal. |
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| 2. |
If 193000 coulomb of electricity is passed through a metallic wire, how many electrons will flow through the wire ? |
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Answer» SOLUTION :1F = 96500C electricity contains 1 MOL or `6.023 xx 0^(23)` no. of ELECTRONS. `therefore ` 193000C = 2 F electricity contains 2 mol or `2xx6.023xx10^(23)` no. of electrons. |
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| 3. |
If 16 g of H_(2) and 56 g of N_(2) are present in a 2 liter vessel at STP then the total number of molecules in the vessel will be |
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Answer» ` 6.022 XX 10^(23)` |
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| 4. |
If 1.71 g of sugar (molar mass=342) is dissoved in 500 cm^(3) of a solution at 300K. What will be its osmotic pressure? |
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Answer» Solution :MASS of solute=`W_(2)=1.71g"Molar mass of solute"=M_(2)=342` Volume of solution=500`CM^(3)=0.5L`Temperature=300K R=0.083 L bar `mol^(-1)K^(-1)` Formula: `pi=(W_(2)RT)/(M_(2)V)` `pi=(1.71xx0.083xx300)/(342xx0.5)` answer `pi=0.249` bar. |
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| 5. |
If 1.5 moles of oxygen combine with Al to form Al_2O_3 , the mass of Al in g (Atomic mass of Al = 27] used in the reaction is |
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Answer» 2.7 Amount of AL that combines with 3 moles of `O_2` =108 g Amount of Al that combines 1.5 moles of `O_2 = 54 g ` |
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| 6. |
If 1.5 moles of oxygen combine with Al to form Al_(2)O_(3), the mass of Al in g (Atomic mass of Al = 27 ) used in the reaction is |
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Answer» 2.7 3 moles of `O_(2)` combine with Al = 4 moles `=4xx27g=108g` `THEREFORE"1.5 moles of "O_(2)" will combine with Al = 54 G."` |
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| 7. |
If 15 gm of a solute in 100 gm of water makes a solution that freezes at -1.0 ^(@) C ,then 30 gm of the same solution the freezes at |
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Answer» `-0.5^(@) C` |
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| 8. |
If 12.6 of NaHCO_(3) is added to 20.0g of HCl solution, the residue solution is found to weigh 24.0g. What is the mass and volume of CO_(2) released at NTP in the reaction? |
| Answer» SOLUTION :8.6g `CO_(@)` relased, VOLUME at NTP `=(22.4)/(44)xx8.6=4.378`. | |
| 9. |
If 15 Faraday quantity of electricity is passed through Al_((l))^(3+) solution then how many gram of Al metal will be obtained ? (cell effeciency is 80%)(at wt. Al = 27 gm"mol"^(-1)) |
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Answer» 135 gm `therefore ` 1 Faraday of electricity DEPOSITES 9 G of Al `therefore ` 15 Faraday will PRODUCE 135 g of Al. If cell efficiency is 80% then `(80xx135)/(100)` =108 g of Al. |
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| 10. |
If 12g of a sample is taken, then 6g of a sampledecays in 1 hr. Findthe amount of sample showing decay in next hour. |
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Answer» 3g |
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| 11. |
If 10gm of water4 is added to 150gm of oleum (104.5%), then the find solution: |
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Answer» Mass of `SO_(3)` left is 10gm 150gm convert into pure `(104.5)/(100)xx150=156.75gm H_(2)SO_(4)` and `w_(H_(2)O)` requried `=(4.5)/(100)xx150=6.75gm` we add water `gt6.75gm` THUS no `SO_(3)` REMAIN after 10gm water addition labelling of new solution `=100%` as no `SO_(3)` left in it. |
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| 12. |
If 10^(21) molecules are removed from 200 mg of CO_(2), then the number of moles of CO_(2), then the number of moles of CO_(2) left are |
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Answer» `2.88xx10^(-3)` `=(0.2)/(44)xx6.023xx10^(23)` molecules After removing `10^(21)` molecules, molecules left `=(2.738-1)10^(21)=1.738xx10^(21)` molecules `=(1.738xx10^(21))/(6.022xx10^(23))mol=2.88xx10^(-3)mol.` |
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| 13. |
If 10^(21) molecules are removed from 100mg CO_(2). Then number of moles of CO_(2) left are: |
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Answer» `6.10xx10^(-4)` `=("Mass ")/("Molar mass")xx6.023xx10^(23)` `=(0.1)/(44)xx6.023xx10^(23)` `=1.368xx10^(21)` Molecules REMAINING `=1.368xx10^(21)-10^(21)=0.368xx10^(21)` Number of moles remaining `=(0.368xx10^(21))/(6.023)xx10^(23)=6.1xx10^(-4)` |
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| 14. |
If 1000 ml of a gas A at 600 torr and 500 ml of gas B at 800 torr are placed in a 2L flask, the final pressure will be |
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Answer» 500 TORR Pressure of gas A in 2L flask`= ( 1000 xx 600)/( 2000) = 300` torr Pressure of gas B in 2L flasks `= ( 500 xx 800)/( 2000) = 200 ` torr Total pressure `= 300 + 200 = 500 ` torr |
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| 15. |
If 100 ml of 1.0 M NaOH solution is diluted to 1.0 L, the resulting solution contains |
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Answer» 1.0 mol of NaOH `1.0xx100=M_(2)xx1000` or `M_(2)=(1.0xx100)/(1000)=0.1` `:. 0.1` MOLE of NaOH is PRESENT in 1.0 L solution. |
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| 16. |
If 100 ml of 0.1 M CH_3COOH and 200 ml of 0.03 M NaOH solutions are mixed together, then the pH of resulting mixture will be given [pk_a (CH_3COOH) = 4.74 and log 1.5 = 0.18)] |
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Answer» 3.97 |
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| 17. |
If 10.0 g of a non-electrolyte dissolved in 100 g of water lowers the freezing point of water by 1.86^(@)C, the molar mass of the non-electrolyte is ( K_(f)=1.86 Km^(-1)) |
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Answer» `10.0` `=(1.86xx1000xx10.0)/(100xx1.86)=100` |
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| 18. |
If 1.0 mole of I_(2) is introduced into 1.0 litre flask at 1000 K, at quilibrium (K_(e )=10^(-6)), which one is correct ? |
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Answer» `[I_(2)(g)] gt [1^(-1)(g)]` `K_(E )=((2x)^(2))/((1-x))=10^(-6)` So In. shows that `(1-x)gt 2x therefore [I_(2)(g)] gt [I^(-)(g)]` |
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| 19. |
If 10 ml of 0.1 M aqueous solution of NaCl is divided into 1000 drops of equal volume. What will be the concentration one drop |
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Answer» 0.01 M |
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| 20. |
If 10 mL of 0.1 M aqueous solution of NaCl is divided in to 1000 drops of equal volume, what will be the concentration of one drop ? |
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Answer» 0.01 M |
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| 21. |
If 1.0 kcal of heat is added to 1.2 L of O_(2) in a cylinder of constant pressure of 1 atm, the volume increases to 1.5 L. Calculate DeltaEandDeltaH of the process. |
| Answer» SOLUTION :`DeltaE=0.993"KCAL",DeltaH=1"kcal"` | |
| 22. |
If 10^(-4)dm^(3) of water is introduced into a 1.0dm^(3) flask at 300 K, how many moles of water are in the vapour phase when equilibrium is established? (Given : Vapour pressure of H_(2)O at 300 K is 3170 Pa, R=8.314JK^(-1)mol^(-1)) |
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Answer» `5.56xx10^(-3)` MOL |
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| 23. |
If 1 mole of I_2 is introduced into 1.o litre flask at 1000 K, at equilibrium (K_c = 10^-6) which one is correct ? |
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Answer» [I_2(G)]GT`[I^-(g)]` |
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| 24. |
If 1 mole H_(2) is reacted with 1 mole of the following compound. Which double bond will be hydrogenated ? |
| Answer» SOLUTION :N//A | |
| 25. |
If 1 mole of an ideal gas exapands isothermally at 37^(@)C from 15 L to 25L, the maximum work obtained is |
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Answer» 12.87 L atm `=-2.303xx1xx0.0821xx(273+37)XX"log"(25)/(15)` `=-2.303xx0.0821xx310xx"log"(5)/(3)` `=13J~~12.87L atm` |
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| 26. |
If 1 mL of a KMnO_(4) solution react with 0.140g Fe^(2+) and if 1 mL of KHV_(2)O_(4). H_(2C_(2)O_(4) solution react with o.1 mL of previous KMnO_(4) solution, how many millilitres of 0.20 M NaOH will react with 1 mL of previous KHC_(2)O_(4). H_(2)C_(2)O_(4) solution in which all the protons (H^(+)) are ionisable ? |
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Answer» 15/6 mL |
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| 27. |
If 1 ml of water contains 20 drops. Then no. of molecules in a drop of water is |
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Answer» `6.023xx10^(23)` molecules 1 ml of water contains `=(6.023xx10^(23))/22400` molecules `=20` drops `:.` 1 drop of water will contain `=(6.023xx10^(23))/(224xx2xx10^(3))` `=1.344xx10^(18)` molecules. |
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| 28. |
If 1 mL of water contains 20 drops, then number of molecules in a drop of water is |
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Answer» `6.023xx10^(23)` `therefore" 20 drops of "H_(2)O=1 g` `therefore" 1 drop of "H_(2)O=(1)/(20)g=0.05g` `=(0.05)/(18)"mole"=(0.05)/(18)xx6.022xx10^(23)" molecules"` `=1.673xx10^(21)` molecules. |
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| 29. |
If 1 microgram of radium has disintegrated for 500 years, how many alpha particles will be emitted per second |
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Answer» `2.92 xx 10^(4) //s` |
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| 30. |
If 1 M CH_3COOHNa is added to 1M CH_3COOH: |
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Answer» PH of the SOLUTION increases |
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| 31. |
If 1 litre of N2 at 27^(@)C and 760 mm Hg contains N molecules, 4 litres of O_(2) under the same conditions of temperature and pressure, shall contain |
| Answer» Answer :D | |
| 32. |
If 1 grain is equal to 64.8mg, how many moes of aspirin (mol. Wt. =169) are present in a 5 grain aspirin tablet? |
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Answer» SOLUTION :Mass of ASPIRIN in the tablet =`64.8xx5=324mg` =0.324g NUMBER of moles `=("Mass")/("Molar mass")=(0.324)/(169)` `=1.92xx10^(-3)` |
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| 33. |
If 1 faraday of electricity is passed through a solution of CuSO_4 the amount of copper deposited will be equal to its : |
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Answer» GRAM EQUIVALENT weight |
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| 34. |
If 1/2 moles of oxygen combine with aluminium to form Al_(2)O_(3) then weight of Aluminium metal used in the reaction is (Al = 27 ) |
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Answer» 27 g |
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| 35. |
If 0.75 mole of an ideal gas expands isothermally at 27^(@)C from 15 litres to 25 litres, the maximum work obtained is |
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Answer» 8.40 J |
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| 36. |
If 0.561 g KOH is dissolved in water to give 200mL of solution at 298 K, calculate the concentration of potassium, hydrogen and hydroxyl ions. What is the pH ? |
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Answer» SOLUTION :`[KOH]=0.561/56 times1000/200M=0.050M` `As KOH toK^+ +OH^-,therefore[K^+][OH^-]=0.05M` `[H^+]=K_w//[OH^-]=10^-14//0.05=10^-14//(5 times10^-2)=2.0 times10^-13M` `pH=-LOG[H^+]=-log(2.0 times10^-13)=13-0.3010=12.699` |
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| 37. |
If 0.50 mol of CaCl_(2) is mixed with 0.20 mol of Na_(3)PO_(4), the maximum number of moles of Ca_(3)(PO_(4))_(2) which can be formed, is |
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Answer» `0.70` `therefore` 2Moles of `Na_(3)PO_(4)=3` mole of `CaCl_(2) = 1` mole `Ca_(3)(PO_(4))_(2)` `therefore 0.2` mole of `Na_(3)PO_(4)=0.3` mole of `CaCl_(2)=0.1` mole of `Ca_(3)(PO_(4))_(2)`. |
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| 38. |
If 0.5 mole of BaCl_(2) is mixed with 0.2 mole of Na_(3)PO_(4) the maximum number of mole of Ba_(3)(PO_(4))_(2) that can be formed is |
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Answer» `0.7` |
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| 39. |
If 0.5 mole of BaCl_2 is mixed with 0.2 mole of Na_3PO_4the maximum number of mole ofBa_3(PO_4) that can be formed is : |
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Answer» 0.7 |
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| 40. |
If 0.5 mol of BaCl_(2) is mixed with 0.2 mole of Na_(3)PO_(4), the maximum number of moles of Ba_(3)(PO_(4))_(2) that can be formed is |
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Answer» 0.7 `"3 moles of "BaCl_(2)" react with 2 moles of "Na_(3)PO_(4).Na_(3)PO_(4)" will be the LIMITING reactant."` |
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| 41. |
If 0.5 amp current is passed through acidified silver nitrate solution for 100 minutes the mass of silver deposited on cathode, is (eq. wt. of silver nitrate=108) : |
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Answer» 2.3523 g TIME (t)=100 MM `=100xx60 sec.=6000 s`. EQ. MASS of Ag (E ) =108 `W=(EIt)/(96500)=(108xx0.5xx6000)/(96500)=3.3575 g`. |
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| 42. |
If 0.5 g of a solute (molar mass 100 g mol^(-1)) in 25 g of solvent elevates the boiling point by 1 K, the molar boiling point constant of the solvent is |
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Answer» 2 `K_(b)=(1xx100xx25)/(0.5xx1000)=5.00` |
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| 43. |
If 0.4 gm NaOH is present in 1 litre solution, then its pH will be |
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Answer» 2 `[H^(+)] = 10^(-12), pH = -log[H^(+)] = 12`. |
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| 44. |
If 0.228 g of silver salt of dibasic acid gabe a residue of 0.162 g of silver on ignition then molecular weight of the acid is |
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Answer» 70 Mass of silver LEFT `= 0.162gm` Basicity of ACID `= 2` Step 1 : To calculate the EQUIVALENT mass of the silver salt (E ). `(" Eq.mass of silver salt")/(" Eq. mass of silver ") = (" Mass of acid taken ")/(" Mass of silver left ")` `= E/ 108 = (0.0228)/(0.162)` `= E = (0.228)/(0.162) xx 108 = 152` (Eq. mass of silver salt) Step 2. to calculate the eq. mass of acid . Eq. mass of acid = Eq. mass of silver salt - Eq. mass of Ag + Basicity `= 152- 108 +1 = 152 - 107 = 45` (Eq. mass of acid) Step 3 : To determine the molecular mass of acid. Mol. mass of the acid = Eq. mass of acid `xx` basicity `= 45 xx 2 = 90`. |
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| 45. |
If 0.20 g chloride of a certain metal, when dissolved in water and treated with excess of AgNO_(3) yields 0.50 g of AgCl, the equivalent mass of the metal is (Ag=108, Cl = 35.5) |
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Answer» 21.9 `=(0.2)/(0.5) implies E = 21.90` |
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| 46. |
If 0.2g of a gas 'X' occupies a volume of 440 ml and if 0.1 g of CO_(2) gas occupies a volume of 320 ml at the same temperature and pressure , X could be |
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Answer» `O_(2)` `( V_(1))/( V_(2))= ( n_(1))/(n_(2)) = ( W_(1)//M_(1))/(W_(2)//M_(2))` `( 440 ML )/( 320ml ) = ( 0.2 //M_(1))/( 0.1 // 44 )` `:. M _(1) = 66g mol^(-1)` Hence gas X could be `SO_(2)` |
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| 47. |
If 0.2 mol of O_(2) vapours can effuse from an opening in a heated vessel in 20 second how long will it take 8 gm H_(2) (g) to effuse under same conditions. |
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Answer» `600 sec` `((DELTA n)/(t))_(o_(2))/(((Delta n)/(t))_(H_(2))) = sqrt((2)/(32))` `((0.2)/(20))/((4)/(t)) = sqrt((1)/(16))` `t = (400)/(4) = 100 sec` |
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| 48. |
If 0.2 mol of H_(2(g)) and 2.0 mol of S_((s)) are mixed in a 1dm^(3) vessel at 90^(@)C, the partial pressure of H_(2)S_((g)) formed according to the reaction H_(2(g))+S_((s))iffH_(2)S,K_(p)=6.8xx10^(-2) would be |
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Answer» <P>0.19 ATM `[H_(2)]=(0.2-x),[H_(2)S]=x` `p_(H_(2))=(0.2-x)/(0.2-x+x)=(x)/(0.2)xxP` `K_(p)=(p_(H_(2)S))/(p_(H_(2)))i.e.,6.8xx10^(-2)=(x)/((0.2-x))` or, `0.068(0.2-x)=xorx=0.0127mol` Pressure of 0.0127 mol of `H_(2)S` at 363 K in 1 L vessel, `P=(NRT)/(V)=(0.0127xx0.0821xx363)/(1)=0.38atm` |
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| 49. |
If 0.2 g of fine animal charcoal is mixed with half litre of acetic acid (1 M) solution and shaken for 30 minutes |
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Answer» CONCENTRATION of the solution REMAINS same |
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| 50. |
If 0.2 ampere can deposit 0.1978 g of copper in 50 minutes, how much of copper will be deposited by 600 coulombs? |
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Answer» 19.78 g |
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