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.
| 51101. |
40 ml of a hydrocarbon undergoes combustion in 260 ml oxygen and gives 160 mlof CO_(2). If all volumes are measured under similar conditions of temperature and pressue, the formula of the hydrocarbon is |
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Answer» `C_(3)H_(8)` `40 ml-260 ml-160 ml` |
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| 51102. |
40 ml of 0.1 Mammonia is mixed with 20 ml of 0.1 M HCl. What is the pH of the mixture ? ( pK_(b) of ammoniasolution is 4.74) |
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Answer» Solution :40 ml of 0.1 M `NH_(3)` solution `= 40xx0.1` millimole = 4 millimoles `NH_(4)OH+HCl rarr NH_(4)CL + H_(2)O` 2 millimole of HCl will NEUTRALIZE 2 millimoles of `NH_(4)OH` to form 2 millimoles of `NH_(4)Cl`. `NH_(4)OH` left = 60 ml `:. [NH_(4)OH]=(2)/(60)M, [NH_(4)Cl]=(2)/(60)M` `pOH=pK_(b)+LOG .([NH_(4)Cl])/([NH_(4)OH])` `=4.74 + log .(2//60)/(2//60)=4.74` `:. pH=14-4.4.74=9.26` |
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| 51103. |
40 ml gaseous mixture of CO, CH_(4) and Ne was exploded with 10 ml of oxygen. On cooling, the gases occupied 36.5 ml. After treatment with KOH the volume reduced by 9 ml and again on treatment with alkaline pyrogallol, the volume further reduced, percentage of CH_(4) in the original mixture is |
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Answer» a. `22.4` `underset(y)(CH_(4))+underset(2y)(2O_(2))rarrunderset(y)(CO_(2))+2H_(2)O` On passing through KOH, volume decrease due to `CO_(2)` absorption `impliesx+y=9….(1)` Final volume after reaction = `CO_(2)+Ne+"left over "O_(2)` `=(x+y)+(40-x-y)+(10-x//2-2y)` `36.5=50-(x)/(2)-2y` `x+4y=27....(2)` solving, `y=6,x=3` `IMPLIES %" of "CH_(4)=(6)/(40)xx100=15%` |
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| 51104. |
40 mL of 0.05 M Na_(2)CO_(3). NaHCO_(3). 2H_(2)O (sesquicarbonate ) is titrated against 0.05 M HCl. X and of HCl is used when phenolphthalein is the indicator in two separate titrations , hence (y-x) is : |
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Answer» 80 mL |
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| 51105. |
40 gm of a carbonate of an alkali metal or alkaline earth metal containg some insert impurities was made to react with excess HCl solution. The liberated CO_(2) occupied 12.315 litre at 1 atm and 300K. The corrrect option is: |
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Answer» Mass of IMPURITY of 1gm and METAL is Be |
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| 51106. |
40 gm NaOH, 106 gm Na_(2)CO_(3) and 84 gm NaHCO_(3) is dissolved in water and the solution is made 1 lit, 20 ml of this stock solution is titrated with 1 N HCl, hence which of the followign statements are correct? |
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Answer» The burette reading of HCl will be 40 ML, if phenolphthalein is used as indiator from the beginning a) In presence of Hph, Eqts of `NaOH+(1)/(2)` EQ `N_(2)CO_(3)` = Eq HCl `(200xx1xx1)+(1)/(2)(20xx1xx2)=1xxV` `V_(HCl)=40ml` c) In presence of methyl orange at first end point `(1)/(2)` eq `NA_(2)CO_(3)+` eq `NAHCO_(3)=` eq HCl `((1)/(2)xx20xx1xx2)+(20xx1xx1)=V_(HCl)XX1` `V_(HCl)=40ml` d) If methyl orange used Eq `NAOH+` Eq `NAl_(2)CO_(3)+` Eq `NaHCO_(3)` = Eq HCl `(20xx1xx1)+(20xx1xx2)+(20xx1xx1)` `=V_(HCl)xx1impliesV_(HCl)=80` |
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| 51107. |
4.0 g of NaOH are dissolved per litre. Find (i) molarity of the solution (ii) OH^(-)ion concentration (iii) pH value of the solution (At. Masses : Na = 23, O=16, H=1). |
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Answer» Solution :(i) Calculation of molarity : Mass of NaOH DISSOLVED = 4.0 G/LITRE Mol . Mass of NaOH = 40 `:.` Molarity of the solution `= ("Strength in g // litre")/("Mol . Mass") = (4.0)/(40) = 0.1 M` (II) Calculation of the `OH^(-)` ion conc. NaOH completely ionizes as : `NaOH rarr Na^(+) + OH^(-)" " :. [OH^(-)]=[NaOH]=0.1 M = 10^(-1)M` (iii) Calculationof pH : We know that `[H_(3)O^(+)][OH^(-)]=K_(w)=1.0xx10^(-14)` `:. [H_(3)O^(+)]=(K_(w))/([OH^(-)])=(1.0xx10^(-14))/(10^(-1))=10^(-13)M" " :. pH = - LOG [H_(3)O^(+)]= - log 10 ^(-13) = 13`. |
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| 51108. |
4.0 g of argon (at mass = 40) in a bulb at a temperature of TK had a pressure P atm. When the bulb was placed in hotter bath at a temperature 50^(@) more than the first one, 0.8 g of gas had to be removed to get the original pressure. T is equal is |
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Answer» 510 K `PV = w (RT)/(M) " or " WT = (PV)/(R) .M` or `w_(1)T_(1) = w_(2) T_(2)` when P and V are constant Hence `4 xx T = 3.2 (T + 50)` or `T = 200 K` |
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| 51109. |
40 g f a gas occupies 20 dm^(3) at 300 K and 100 kPa pressure. If the pressure is changed to 50 lPa without changing to temperature, what would be its volume ? |
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Answer» Solution :`P_(1)v_(1)=P_(2)v_(2)` at constant temperature. `P_(1)=100 kPa, v_(1)=20 dm^(3), P_(2) =50 kPa, V_(2) ?` `V_(2)=(P_(1)V_(1))/(P_(2)),v_(2)=(100xx20)/(50)=40 dm^(3)` `:. V_(2)=40 dm^(3)` |
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| 51110. |
4-Oxobutanoic acid is reduced with Na-borohydride and the product is treated with aqueous acid. The final product is : |
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Answer»
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| 51111. |
4-Pentenoic acid when treated with I_(2) and NaHCO_(3) gives: |
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Answer» 4,5-diiodopentanoic acid |
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| 51112. |
4 mole of NH_(4) OH and 1 mole of H_(2) SO_(4) are mixed and dilute to 1 lit solution . The pK_(b) of NH_(4) OH is 4.8 . The pH of solution is |
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Answer» `4.8` |
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| 51113. |
4-Methylbenzenesulphoic acid reacts with sodium acetate to give |
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Answer»
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| 51114. |
4-methyl-pent-2-yne has how many sigma and pi bond? |
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Answer» `15 sigma, 2pi` |
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| 51115. |
4-methyl benzene sulphonic acid reacts with sodium acetate to give |
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Answer»
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| 51116. |
4-Methyl-1,3-pentadiene react with HBr, The possible products obtained are |
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Answer» 4-Bromo-2-methyl-2-pentene |
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| 51117. |
4 litres of water are added to 2 litres 6 molar hydrochloric acid solution. What is the molarity of the resulting solution ? |
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Answer» By APPLYING molarity equation : `overset(("dilute"))(M_(1)V_(1))-=overset(("conc."))(M_(2)V_(2))` `M_(1)xx6=6xx2orM_(1)=(6xx2)/(6)=2M`. |
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| 51118. |
4 L of 0.02 M aqueous solution of NaCl was diluted by adding one litre of water.The molality of the resultant solution is : |
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Answer» `0.004` |
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| 51119. |
4-hydroxyl phenol reacts with acidified potassium dichromate to give ……………. |
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Answer» QUINOL |
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| 51120. |
4-hydroxy phenol reacts with acidified potassium dichromate to gives .............. |
| Answer» SOLUTION :p-Benzoquinone | |
| 51121. |
4- heptanoneoverset(KMnO_(4)//H^(+)//Delta)rightarrowA+B. Identify A and B |
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Answer» ETHANOIC ACID pentanoic acid
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| 51122. |
4^(@) hydrogen is not possible, give reasons….. |
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Answer» CARBON has FOUR covalent bond. |
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| 51123. |
4 grams of each pure huydrochloric acid and pure caustic soda are together dissolved in water. What weight of sodium chloride is obtained? |
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Answer» Solution :The STOICHIOMETRIC equation is given as `HCl+NaOH to NaCl+H_(2)O` 1 mole of HCl =1 mole of NaOH 36.5 grams of HCl=40 grams of NaOH NaOH is the limiting reagent. Therefore, the WEIGHT of NaCl obtained is LIMITED by NaOH 1 mole of NaOH=1 mole of NaCl 10 grams of NaOH=58.5 grams of NaCl 4 grams of NaOH=? The weight of sodium CHLORIDE obtained `=58.5 xx (4)/(40)=5.85"grams"` |
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| 51124. |
4 grams of copper chloride on analysis were found to contain 1.890 g of copper (Cu) and 2.110 g of chlorine (CI). What is the empirical formula of copper chloride? |
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| 51125. |
4 grams of each pure hydrochloric acid and pure caustic soda are together dissolved in water. What weight of sodium chloride is obtained? |
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| 51126. |
4 grams of an ideal gas occupies 5.6035 litres of volume at 546 K and 2 atm, pressure. What is its molecular weight ? |
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Answer» 4 |
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| 51127. |
A container of 1 L capacity contains a mixture of 4 g of O_(2) and 2 g H_(2) at 0 .^(@)C . What will be the total pressure of the mixture ?(a) 50 . 42 atm(b) 25 . 21 atm(C) 15 . 2 atm(d) 12 . 5 atm |
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Answer» <P> SOLUTION :Calculation of TOTAL pressure :ACCORDING to Dalton.s law of partial pressure, the total pressure of the gaseous mixture is given by `P_(mixture) = P_(O_2)+P_(H_2) = 2.80 + 22.4 = 25.2` atm |
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| 51128. |
4 gm NaOH dissolve in 250 ml water and solution is prepared. Find molarity of the solution. |
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| 51129. |
4 g of O_2 and 2g of H_2 are confined in a vessel of capacity 1 litre at 0^@C. Calculate the partial pressure of each gas, and |
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Answer» Solution :CALCULATION of partial pressures : Volume of vessel = 1 L, `T = 0^@C = 273 K` `:. "" PV = nRT " or " p = (nRT)/V` `:.` Partial pressure of oxygen `Po_2=(nRT)/V =( 0.125 xx 0.0821 xx 273)/1 = 2.80` atm Similarly, partial pressure of hydrogen `P_(H_2)= (nRT)/V= (1xx0.0821 xx 273)/1= 22.4` atm |
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| 51130. |
4 g of O_2 and 2g of H_2 are confined in a vessel of capacity 1 litre at 0^@C. Calculate the number of moles of each gas |
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Answer» SOLUTION :CALCULATION of number of moles : Number of moles = `("Mass in grams")/("GRAM molecular mass")` `:. " Number of moles of " O_2 = 4/32 =0.125` and, Number of moles of `H_2 =2/2 =1` |
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| 51131. |
4 g of NaOH are dissolved in 200 cm^3 of water. Find the molarity of the solution. |
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Answer» Solution :Mass of NaOH dissolved = 4g Molecular mass of NaOH = 23 + 16 +1 = 40 `THEREFORE` Moles of NaOH dissolved `=4/40 = 0.1` Volume of water taken `=200 cm^(3) = 200 xx 10^(-3) L` The molarity of the solution `=("No. of moles of NaOH")/("Volume in litres")` `=0.1/(200 xx 10^(-3))` `=0.5 mol L^(-1)` Hence, the given solution is 0.5 M |
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| 51132. |
4 g. of methane at 380 torr and 273^@C occupies a volume of |
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Answer» 5.6 L |
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| 51133. |
4 g of a mixture of Na_(2)SO_(4) and anhydrous Na_(2)CO_(3) were dissolved in pure and volume made up to 250 mL. 20 mL of this solution required 25 mL of N//5 H_(2)SO_(4) for complete neutralisation. Calculate the percentage composition of the mixture. |
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| 51134. |
4 g of a mixture of NaCl and Na_(2)CO_(3) were dissolved in water and volume made up to 250 mL. 15 mL of this solution required 50 mL of N//10 HCl for complete neutralisation. Calculate the percentage composition of the original mixture. |
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| 51135. |
4g of mixture of Na_(2)CO_(3) and NaHCO_(3) on heating liberates 448 ml of CO_(2) at STP. The percentage of Na_(2)CO_(3) in the mixture is |
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Answer» 84 |
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| 51136. |
4 g / L solutionof NaOH is given. The molarity of the solution is ........... M. (Molecular mass of NaOH =40 g / mol) |
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Answer» 160 |
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| 51137. |
4 g Cu is dissolved in concentrated HNO_(3). On heating this solution 5 g oxide will be obtained Then the equivalent weight of Cu is..... |
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Answer» 23 4 g Cu COMBINE with `(5-4)=1G` oxygen `:.1 g O RARR Cu "" :. 8 g rarr (?)` ` = (8xx4)/(1) = 32 g Cu` eq. wt `=32 "g eq. wt"^(-1)` |
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| 51138. |
3s orbital has 2 radial nodes |
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| 51139. |
3O_(2) harr 2O_(3). Oxygen is ozonised until the partial pressures of both gases become equal at equilibrium. Which statements are correct if P_(eq) = 10 atm ? |
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Answer» 60% oxygen is ozonised by volume PARTIAL PRESSURES are EQUAL `implies 1-ALPHA=(2alpha)/(3) implies alpha=(3)/(5)=60%` `(D)/(d)=1+(n-1)alpha=1+((-1)/(3))alpha` `(32)/(d)=(4)/(5), d=40` `2P=P_(eqm) implies P=(10)/(2)=5` `:. K_(P)=(P^(2))/(P^(3))=(1)/(P)=0.2 atm^(-1)` |
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| 51140. |
3N H_(3)PO_(4) aqu. solutionis given = .......... gm/litre. |
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Answer» 98 `N=("gm/lit")/("equ.wt.")= 3 XX (98)/(3) = 98` |
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| 51141. |
3L Mixture of propane and butane on complete combustion at 298K and 1atm gave 10L CO_2. Calculate the composition of gas |
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Answer» `1L C_(3)H_(8), 2L C_(4)H_(10)` |
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| 51142. |
3Fe_((s)) + 4H_2O_((g)) undersetlarrto 3Fe_3O_(4(s)) + 4H_2O_((g)) formula of K_P and K_C is ……………. |
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Answer» SOLUTION :`{:(,3Fe_((s)) + 4H_2O_((g)) UNDERSETLARRTO,Fe_3O_(4(s)) + 4H_2O_((g))),("Current reaction:", 3Fe_((s)) + 4H_2O_((g)) undersetlarrto , Fe_3O_(4(s))+4H_(2(g))):}` `K_c=[H_2]^4/[H_2O]^4` `K_p=(p_(H_2))^4/(p_(H_2O))^4` |
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| 51143. |
3Cl_(2)+6NaOHrarr5NaCl+NaClO_(3)+3H_(2)O, chlorine gets |
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Answer» Oxidised |
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| 51144. |
3CIO^(-)(aq)rarrCIO_(3)+2C^(-) is an exameof |
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Answer» oxidation reaction |
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| 51145. |
3Ca_(3)(PO_(4))_(2).CaF_(2) is a part of enamel on teeth. |
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Answer» |
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| 51146. |
3C_(2)H_(2) hArr C_(6) H_(6) the above reaction is performed in a I lit vessel. Equilibrium is established when 0.5 mole of benzene is present at certain tempe-rature. If equilibrium constant is 4 lit^(2) "mole"^(-2) The total number ot moles of the substances present at cquilibrium, |
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Answer» 0.5 `K_(C)=([C_(6)H_(6)])/([C_(2)H_(2)]^(3)), 4=(0.5)/([C_(2)H_(2)]^(3)) implies [C_(2)H_(2)]^(3)=(1)/(8)` `[C_(2)H_(5)]=0.5=(n)/(v) implies n=0.5` Total no. of moles of `C_(2)H_(2)` & `C_(6)H_(6)` at equilibrium = 0.5+0.5=1 |
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| 51147. |
3.92 g of ferrous ammonium suphate ar dissolved in 100 Ml water 20 ml of this solution requires 18 complete oxidation the weight of KMnO_(4) present in one litre of the solution is |
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Answer» 34.76 G `MnO_(4)^(-)+5Fe^(2+)+8H^(+)rarr5Fe^(3+)+MN^(2+)+4H_(2)O` Mol WT of ferrous ammonium suphate `(NH_(4))SO_(4)FeSO_(4)6H_(23)O=392` applyinhg molarity equation `=(M_(2)V_(2))/(n_(2))` or `(0.1xx20)/(5)=(M_(2)xx18)/(1)` or `M_(2)=(0.1xx20)/(5xx18)=(M)/(45)` Amount of `KMnO_(4)` present in one litre =Molarity x mol wt `1/45xx158=3.51` g since 3.476 g isclose to 3.51 g therefore option (d) is correct |
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| 51148. |
38 cm^(2) N_(2) gas at 300K temperature and 96pa pressure. In 0.25g organic compound calculate the % of nitrogen. (1 atm .- 101.3 pa) |
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| 51149. |
3.7 g of a gas at 25°C occupies the same volume as 0.184 g of hydrogen at 17°C and at the same pressure. What is the molecular mass of the gas ? |
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| 51150. |
3.65% W/V HCl solution has density 1.0365 gm/cc, then its concentration is |
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Answer» 1 M `m=(1000M)/(1000d-MM_(1))=(1000)/(1036.5-36.5)=1m` |
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