InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 88551. |
A mixture of chloroform and acetone forms a solution with negative deviation. Why? |
Answer» SOLUTION :A HYDROGEN bond is FORMED between ACETONE and CHLOROFORM as shown below :
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| 88552. |
A mixture of chlorides of copper, cadmium, chromium, iron and aluminium was dissolved in water acidified with HCl and hydrogen sulphide was was passed for sufficient time. It was filtered, boiled and a few drops of nitric acid were added while boiling. To this solution ammonium chloride and sodium hydroxide were added in excess and filtrate shall give test for- |
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Answer» SODIUM ion |
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| 88553. |
A mixture of CH_4steam on passing over nickel suspension on alumina at 800^@Cgives : |
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Answer» CO only |
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| 88554. |
A mixture of CH_(4) & O_(2) is used as an optimal fuel if O_(2) is present in thrice the amount required theoretically for combustion of CH_(4). Calcualte the number of effusions steps required to convert a mixture containing1 part of CH_(4) in 193 parts mixture ( parts by volume) . If calorific value (heat evolved when 1 moleis burnt) of CH_(4) is 100 cal// mole & if after each effusion 90% of CH_(4) is collected,find out what initial mole of each gas in initial mixture required for producing 1000 cal of energy after processing.[Given ( 0.9)^(5) = 0.6 ] |
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Answer» |
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| 88555. |
A mixture of CH_(4) and C_(2)H_(4) was completely burnt in excess of oxygen, yielding equal volumes of CO_(2) and steam. Calculate the percentages of the compounds in the original mixture: |
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Answer» |
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| 88556. |
A mixture of CH_(4) and C_(2)H_(2) occupies a certain volume at a total pressure of 70.5 mm Hg. The sample is burnt, formed CO_(2) and H_(2)O. The H_(2)O is removed and the remaining CO_(2) is found to have pressure of 96.4 mmHg at the same volume and temperature as the original mixture. What mole fraction of the gas was C_(2)H_(2) ? |
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Answer» Solution :Let the number of MOLES of `CH_(4)` and `C_(2)H_(2)` be X and y respectively. `{:(CH_(4),+,C_(2)H_(2),+,O_(2),rarr,CO_(2) ,+,H_(2)O),("x moles",,"y moles",,,,,,):}` Applying POAC for C atoms, `1 xx` moles of `CH_(2) + 2 xx` moles of `C_(2)H_(2) = 1 xx` moles of `CO_(2)` `x + 2y = "moles of " CO_(2)` As no. of moles `alpha` pressure at const. TEMPERATURE and volume. `("no. of moles of " CH_(4) " and "C_(2)H_(2))/("no. of moles of " CO_(2)) = (70.5)/(96.4)` or `(x+y)/(x+2y) = (70.5)/(96.4)` `therefore (y)/(x+y)` = mole fraction of `C_(2)H_(2) =0.368`. |
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| 88557. |
A mixture of carboxylic acids (X) and (Y) cannot be separated by normal methods however when this mixture is treated with optically active quinine give optically active salts (P) and (Q). These two salis can be separated by fractional crystallization, separated and acidified with HCl to form amines and carboxylic acids. What is the diastereoisorner of (+) -tartaric acid ? |
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Answer» (-) - Tartarie ACID |
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| 88558. |
A mixture of carboxylic acids (X) and (Y) cannot be separated by normal methods however when this mixture is treated with optically active quinine give optically active salts (P) and (Q). These two salis can be separated by fractional crystallization, separated and acidified with HCl to form amines and carboxylic acids. The compound (X) and (Y) may be |
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Answer» `CH_(3)COOH, CH_(3)CH_(2)COOH` |
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| 88559. |
A mixture of carboxylic acids (X) and (Y) cannot be separated by normal methods however when this mixture is treated with optically active quinine give optically active salts (P) and (Q). These two salis can be separated by fractional crystallization, separated and acidified with HCl to form amines and carboxylic acids. (P) and (Q) are separated by fractional crystallization due to |
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Answer» DIFFERENCE in BOILING point |
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| 88560. |
A mixture of carboxylic acid (A) and alcohol (B) on heating give and ester (C ) having molecular mass 74. What is (C ) ? |
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Answer» `HCOOC_(2)H_(5)` `(HCO)_(2)O+C_(2)H_(5)OH overset(Delta) to HCOOH + underset("mol. mass 74")(HCOOC_(2)H_(5)) ` |
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| 88561. |
A mixture of carbon monoxide and carbon dioxide is found to have a density of 1.7g/lit at S.T.P. The mole fraction of carbon monoxide is |
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Answer» 0.37 `M_("mix")=X_(CO)xxM_(CO)+(1-X_(CO).M_(CO_2)=X_(CO)xx18+(1-X_(CO))xx44 implies X_(CO)=0.37` |
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| 88562. |
A mixture of camphor and KCI can be separated by : |
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Answer» Sulblimation |
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| 88563. |
A mixture of camphor and calcium sulphate can be separated by : |
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Answer» Crystallisation |
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| 88564. |
A mixture of camphar and benozic acid can be separated by |
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Answer» Chemical method |
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| 88565. |
A mixture of calcium acetate and calcium formate on heating gives : |
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Answer» `CH_3COCH_3` |
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| 88566. |
A mixture of CaCl_2and NaCl weighing 4.44gis treated with sodium carbonate solution to precipitate all the calcium ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get 0.56g of CaO. The percentage of NaCl in the mixture is [Atomic mass of Ca = 40] |
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Answer» 31.5 Moles of CA in `CaCl_(2)` =moles of Ca in `CaCO_(3)` Moles of Ca in `CaCO_(3)`=moles of Ca in CaO `implies(X)/(111)=(0.56)/(56)impliesx(0.56)/(56)xx111=1.11g` [m.wt. of `CaCl_(2)`=111,m.wt. of CaO=56] We know that `NaCl+CaCl_(2)`=4.44 y+1.11=4.44`implies`y=3.33g Percentage of NaCl=`3.33xx(100)/(4.44)`=75% |
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| 88567. |
A mixture of CaCl_(2) and NaCl weighing 4.44 g is treated with sodium carbonate solution to precipitate all the Ca^(2+) ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get 0.56 g of CaO. The percentage of NaCl in the mixture (atomic mass of Ca = 40) is |
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Answer» 75 `underset(111g)(CaCl_(2))+Na_(2)CO_(3)RARR underset(100g)(CaCO_(3))+2NaCl` 111 g `CaCl_(2)` PRODUCE `CaCO_(3)=100g` `therefore"x g "CaCl_(2)" will produce "CaCO_(3)=(100)/(111)xg` `underset(100g)(CaCO_(3))rarrunderset(56g)(CaO)+CO_(2)` 100 g `CaCO_(3)` produce `CaO=56g` `therefore (100x)/(111)g" will produce CaO"=(56)/(100)xx(100x)/(111)` `=(56x)/(111)g` Thus, `(56x)/(111)=0.56"or"x=1.11 g` `therefore %" of NACL in the mixture "=(3.33)/(4.44)xx100=755` Alternatively, `underset(111g)(CaCl_(2))rarrCaCO_(3)rarrunderset(56g)(CaO)` x g `CaCl_(2)` will GIVE `CaO=(56x)/(111)g` `therefore""(56x)/(111)=0.56"(given)or"x=1.11g` |
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| 88568. |
A mixture of CaCl_(2) and NaCl weighing 4.44 g is treated with sodium carbonate solution to precipitate all the Ca^(+2)ions as calcium carbonate The calcium carbonate so obtained is heated strongly to get 0.56 g of CaO . The percentage of NaCl in the mixture (atomic mass of Ca=40) is |
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Answer» A) 75 `underset("100 G")(CaCO_(3))overset(Delta)(to)underset("56 g")(CaO)+CO_(2)` 56 g of `CaO` is obtained from 100 g of `CaCO_(3)" "0.56` g `CaO` is obtained by `(100)/(56)xx0.56=1"g of "CaCO_(3)`. we know that, `underset("111 g")(CaCl_(2))+Na_(2)CO_(3)tounderset("100 g")(CaCO_(3))+2NaCl` 100 g of `CaCO_(3)` is obtained by 111 g of `CaCl_(2)` 1 g of `CaCO_(3)` is obtained by `(111)/(100)=1.11` g of `CaCl_(2)` Weight of `NaCl=4.44-1.11=3.33g` `%` age `NaCl=(3.33)/(4.44)xx100=75%` |
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| 88569. |
A mixture of C_(2)H_(6) and C_(4)H_(4) occupies 40 litres at 1 atm and at 400 K. The mixture reacts completely with 130 g of O_(2) to produce CO_(2) and H_(2)O. Assuming ideal gas behaviour, calculate the mole fractions of C_(2)H_(4) and C_(2)H_(6) in the mixture. |
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Answer» Solution :Let the moles of `C_(2)H_(6)` and `C_(2)H_(4)` be `n_(1)` and `n_(2)` respectively. Applying ideal gas equation, `pV = n RT`, `1 xx 40= (n_(1) + n_(2)) xx 0.0821 xx 400` or, `(n_(1) + n_(2)) = (40)/(0.0821 xx 400)` ……(1) `C_(2)H_(6) + C_(2)H_(4) + O_(2) rarr CO_(2) + H_(2)O` Applying POAC for C, `2n_(1) + 2n_(2)` = moles of `CO_(2)` ......(2) Applying POAC for H, `6 n_(1) + 4n_(2) = 2 xx "moles of " H_(2)O` ........(3) Applying POAC for o, `2 xx (130)/(32) = 2 xx " moles of " CO_(2) + " moles of " H_(2)O` ........(4) From equations(2), (3) and (4) we get, `7 n_(1) + 6n_(2) = (260)/(32)` .......(5) Solving equations (1) and (5) we get, `n_(1) = 0.8168` `n_(2) = 0.4012` `therefore` MOLE FRACTION of `C_(2)H_(6) = (0.8168)/(0.8168 + 0.4012) = 0.67` Mole fraction of `C_(2)H_(4) = 1-0.67 = 0.33`. |
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| 88570. |
A mixture of benzoic acid and naphthalene can be separated by crystallization from : |
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Answer» HOT water |
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| 88571. |
A mixture of benzene and toluene forms : |
| Answer» Answer :A | |
| 88572. |
A mixture of benzaldehyde and formaldehyde when treated with 50% NaOH yields. |
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Answer» Sodium benzoate and sodium formate `H-CHO +C_(6)H_(5)-CHO + NaOH to H-COONa + C_(6)H_(5) -CH_(2)OH` Formaldehyde is more reactive than benzaldehyde. |
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| 88573. |
A mixture of benzaldehyde and formaldehyde on heating with aqueous NaOH solution gives |
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Answer» benzyl ALCOHOL and SODIUM formate. |
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| 88574. |
Amixtureof benzaldehyde and formaldehyde when treated with 50% NaOH yields |
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Answer» sodium benzoate and sodium formate
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| 88575. |
A mixture of benzaldehyde and formaldehyde on heating with aqueous NaO solution gives |
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Answer» BENZYL ALCOHOL and sodium formate In cross Cannizzaro reaction of formaldehyde, formaldehyde is always oxidized. Hence, (A) is the correct answer. |
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| 88576. |
A mixture of benzaldehyde and formaldehyde on heating with aqueous NaOH solution gives : |
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Answer» SODIUM BENZOATE and methyl ALCOHOL |
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| 88577. |
A mixture of benzaldehyde and formaldehyde on heatig with aqueous NaOH solution gives |
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Answer» Benzyl alcohol and SODIUM formate |
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| 88578. |
A mixture of an organic liquid A and water distilled , under one atmospheric pressure at 90.2^(@)C . How many grams of steam will be condensed to obtain 1.0g of liquid A in thedistillate ? (Vapour pressure of water at 99.2^(@)C is 739mm Hg . Molecular weight of A=123) |
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| 88579. |
A mixture of benzaldehyde and acetophenone on heating with dilute NaOH solution gives |
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Answer» Benzolphenone |
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| 88580. |
A mixture of anhydrous ZnCl_(2)+conc.HCI is known as |
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Answer» FEHLING's REAGENT |
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| 88581. |
A mixture of an acid anhydride (A) and a monobasic acid (B) on heating produces another monobasic acid (C) of equivalent weight 74 and an anhydride (D). The acids and anhydrides remain in equilibrium. The anhydride (D) contains two identical flouro alkyls groups. The acid (B) contains a trifluoro methyl group and has an equivalent weight of 128. Give the structures of (A) to D) with proper reasoning (Atomic weight of fluorine 19). |
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Answer» Solution : Acid anhydride (A) +`underset((CF_(3) "group")) ("Monobasic acid (B)")` `hArr`Monobasic acid(C ) +`underset((Two CF_(3) "group")) ("Anhydride(D)")` Eq. wt.=128Eq. wt.=74 Probable formula of acid (B)=`CF_(3)(CH_(2))_(n)COOH` EQUIVALENT weight of (B) =`("MOLECULAR weight")/("BASICITY")` `128=(57+12+14n+12+32+1)/1` n=1 `therefore(B)=CF_(3)CH_(2)COOH` and `(D)=(CF_(3)CH_(2)CO)_(2)O` Similarly, molecular formula of acid (C ) can be calculated to be `CH_(3)CH_(2)COOH`. The reaction, therefore, can be given as, `underset((A))((CH_(3)CH_(2)CO)_(2)O)+underset((B))(F_(3)"CC"H_(2)COOH)hArrunderset((C ))(CH_(3)CH_(2)COOH)+underset((D))((F_(3)"CC"H_(2)CO)_(2)O)` |
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| 88582. |
A mixture of aluminium and zinc weighning 1.67 g was completely dissolved in acid and evolved 1.69 litres of hydrogen at NTP. What was the weight of |
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Answer» Solution :EQ. of METAL= `(0.43)/E ` ( eq. wt of metal `-= `E) `:. ` m.e of metal ` = (0.43)/E xx 1000 = 430/E "" …(Eqn.3)` m.e of total `H_(2)SO_(4)`solution` = 1 xx 50 = 50 "" …(Eqn. 1)` Butm.e of `H_(2)SO_(4)` reacted with metal = m.e of the metal `= (430)/E ` ` :. ` m.e of unreached `H_(2)SO_(4) = ( 50 - 430/E)` Again m.e of unreacted `H_(2)SO_(4)` = m.e of NaOH . ....(Eqn.2) ` :.E = 12.01 ` . |
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| 88583. |
A mixture of aluminium and zincweighning 1.67g was completely dissolvedin acidand evolved 1.69 litres of hydrogen at NTP . What was the aluminium in the original mixture ? (Al = 27, Zn = 65.4) |
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Answer» Solution :Since `H_(2)` is formed by both Al and Zn , EQ. of Al + eq of Zn = eq. of `H_(2)` . Let w be the mass in grams of Al in the MIXTURE. `:. (w)/("eq. wt . of Al") + ((1.67 - w))/(" eq . wt .of Zn") = (1.69)/( " vol. of 1 eq. of " H_(2)" at NT in lit")` ` OMEGA /(27//3) +(1.67 - omega)/(65.4//2) = (1.69)/(11.2){:{("eq . wt of Al"=27/3),("eq. wt. of Zn"=(65.4)/2 ):}}` ` :."" omega = 1.24 g ` |
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| 88584. |
A mixture of alpha-amino acids is obtained when proteins are hydrolysed by |
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Answer» ACIDS |
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| 88585. |
A mixture of Al(OH)_3 and Fe (OH)_3 can be separated easily by treating it with: |
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Answer» HCL |
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| 88586. |
A mixture of alcohol and ether is called : |
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Answer» Natalite |
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| 88587. |
A mixture of Al_(2)O_(3) and Fe_(2)O_(3) can be separated by using |
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Answer» SODIUM hydroxide |
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| 88588. |
A mixture of Al_(2)O_(2) and Fe_(2) can be separated by using |
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Answer» SODIUM hydroxide |
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| 88589. |
A mixture of A(g) and B(g) is formed, where mole fraction of gas A is 0.8. Given : P_(A)^(@) = 400 torr, P_(B)^(@) = 200 torr Mixture of A and B obey Raoult's law.Then : |
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Answer» Composition of first drop of condensate is `(X_(A) = 2/3)` |
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| 88590. |
A mixture of Al_(2) O_(3) and Fe_(2) O_(3) can be separa-ted by using |
| Answer» Answer :A | |
| 88591. |
A mixture of AB_(3)(g) and A_(2)B_(4)(g) is placed in a sealed container. (At. Mass of A = 14 and At. ,mass of B =1 ) The temperature initially maintained is 300K. The total pressure is 0.5 atm. The container is heated to 1200k, when both AB_(3) and A_(2) B_(4) decomposed to A_(2) and B_(2) when the decomposition was complete the pressure observed was 4.5 atm. What is the percentage of AB_(3)(g) in the original mixture ? |
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Answer» |
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| 88592. |
A mixture of acetone and methanol can be separated by : |
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Answer» STEAM distillation |
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| 88593. |
A mixture of acetone and "CCl"_(4) can be separated by |
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Answer» Azoeotropic distillation (B) is correct because `"CCl"_(4)` and acetone DIFFER in their boiling point. (C ) is used only in CASE of steam volatile substance. It is not correct. (d) Vacuum distillation is used in liquids which decompose at their boiling point. `:.` It is not correct. |
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| 88594. |
A mixture of A and B in the molar ratio 1:2 forms a maximum boiling azeotrope. Identify the incorrect statement, if A is more volatile. [ Molar mass of A=100, Molar mass of B=50] |
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Answer» A liquid solution of A and B having mass % of A=50 will have VAPOURS having mass % of A=50. |
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| 88595. |
A mixture of ""^(239)Pu and ""^(240)Pu has a specific activity of 6.0xx 10^(9) dis/s. The half-lives of the isotopes are 2.44 xx 10^(4) and 6.58 xx 10^(3) years, respectively. Calculate the isotopic composition of this sample |
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Answer» Solution :Specific activity means activity per gram. Sp. Activity of `""^(239)Pu= lamda= N = ((0.6932)/(2.44 xx 10^(4))) ((6.022 xx 10^(23))/(239))` `=7.15 xx 10^(16)`/YR/g `=2.27 xx 10^(9)//s//g. (1 yr = 3.15 xx 10^(7)s)` Sp. activity of `""^(240)Pu= ((0.6932)/(6.58 xx 10^(3))) ((6.022 xx 10^(23))/(240))` `=2.64 xx 10^(17)//yr//g= 8.37 xx 10^(9)//s//g` THUS, `(2.27 xx 10^(9)) x + (8.37 xx 10^(9)) (1-x)=6.0 xx 10^(9)` (x=fraction of `""^(239)Pu`) x=0.39 or 39% |
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| 88596. |
A mixture of 2.3 g formic acid and 4.5 g oxalic acid is treated with conc. H_2SO_4. The evolved gaseous mixture is passed through KOH pellets. Weight (in g) of the remaining product at STP will be |
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Answer» 2.8 |
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| 88597. |
A mixture of 20 mL of CO, CH_(4) and N_(2) was burnt in excess of O_(2) resulting in the reduction of 13 mL of volume. The residual gas was then treated with KOH solution to show a contraction of 14 mL in volume. Calculate volume of CO, CH_(4) and N_(2) in the mixture. All measurements are made at constant pressure and temperature. |
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Answer» SOLUTION :`"Suppose volume of CO = a mL," CH_(4)="b mL and N"_(2)="c mL. Then a + b + c = 20 mL…(i)"` The combustion reaction will be `CO+(1)/(2)O_(2)RARR CO_(2)` `CH_(4)+2O_(2) rarr CO_(2)+2H_(2)O(l)` `N_(2)+O_(2) rarr "No reaction"` Thus, a mL of CO will produce `CO_(2)=amL` `"b mL of CH"_(4)" will produce CO"_(2)=bmL` `N_(2)` will remain as such, i.e. = c mL As `CO_(2)` is absorbed by KOH, decrease in volume on treating with KOH will be `=a+b=14mL` (Given) .....(ii) The first given decrease is DUE to `O_(2)` consumed. a mL of CO will consume `O_(2)=(a)/(2)mL` b mL of `CH_(4)` will consume `O_(2)=2bmL` `therefore O_(2)` consumed `=(1)/(2)+2b=13mL"(Given )...(iii)"` From eqns. (i) and (ii), `c = 20 - 14 = 6 mL` From Eqns. (ii) and (iii), `(a)/(2)+2(14-a)=13 "or"(3)/(2)a=15"or"a=10mL` `therefore " From eqn. (ii),"10+b=14"or"b=4mL` `CO=10mL, CH_(4)=4mL, N_(2)=6mL` |
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| 88598. |
A mixture of 2 moles of CO and 1 mole of O_2 in a closed vessel is ignited to convert CO into CO_2. Then |
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Answer» `DeltaH LT DeltaE` |
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| 88599. |
A mixture of 2 moles of carbon monoxide and one mole of oxygen in a closed vessel is ignited to get carbon dioxide. If Delta H is the enthalpy change and Delta U is the change in internal energy, then |
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Answer» `DELTA H GT Delta U` |
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| 88600. |
A mixture of 2 mole of carbon monoxide gas and one mole of dioxyen gas is enclosed in a close vessel and is ignited to convert carbon monoxide into carbon dioxide. If the enthalpy change is DeltaH and internal change is DeltaU, then for the above process. |
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Answer» `DELTAH = DELTAU` |
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