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.
| 51451. |
2 litres of nitrogen completely react with 6 litres of hydrogen under suitable conditions to form 4 litres of NH_3. If all the volumes are measured at the same temperature and pressure, show that the data given are in accordance to the Gay Lussac's law of combining volumes. |
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Answer» Solution :The reaction mentioned in the question takes place as follows : `underset("2 litres")((N_(2)(g)) +underset("6 litres")(3H_(2)(g)) to underset("4 litres")(2NH_(3)(g))` The volumes of the reacting gases are in the ratio 2 : 6, i.e., 1: 3. The product ammonia is ALSO a gas and its VOLUME also bears a simple whole number ratio with the volumes of reactants. The ratio of the volumes of all reactants and product in this reaction is thus 1:3:2 Since, the ratio is a simple whole number ratio, the data are in ACCORDANCE to the Gay Lussac.s law of combining volumes. |
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| 51452. |
2 L of hydrogen and 2.5 L of chlorine are allowed react in diffused light. Write the volume composition of the component gases after reaction. |
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Answer» Solution :Reaction between and chlorine leading to the production of hydrogen chloride is given as `H_(2)+Cl_(2)rarr2HCl` `{:("1 vol","1 vol","2 vol","Gay - Lussac.s volumes"),(2,2.5L,0L,"at START"),(0,0.5L,4L,"after the reaction"):}` The volume of the mixture is 4. 5L Volume of unreacted `Cl_(2)=0.5L` Volume of `HCl` PRODUCED = 4 L |
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| 51453. |
2-iodo-2-methylpropane belongs to …………………. type. |
| Answer» SOLUTION :`3^@`HALOALKANES | |
| 51454. |
2-Hexyne gives trans-2-hexene on treatment with |
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Answer» `Li//NH_3` |
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| 51455. |
2-hexyne give trans-2-hexene on treatment with |
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Answer» `Li//NH_3` |
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| 51456. |
2-Hexyne gives trans-2-Hexene on treatment with : |
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Answer» `Pt//H_(2)` |
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| 51457. |
2 grams of Helium diffuses from a porous plate in 4min. How many grams of CH_4 would diffuse through the same plate in same time under similar conditions? |
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Answer» Solution :`(w_1)/(t_1) xx (t_2)/(w_2) = sqrt((M_1)/(M_2)) IMPLIES 2/(w_2) = sqrt((4)/(16))`. `W_(CH_4) = 4 gm`. |
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| 51458. |
2 grams of a mixture of sodium carbonate and sodium bicarbonate on strong heating liberated carbondioxide, which occupie. 0.224 L at STP. What is the weight of Na_(2)CO_(3) in the original mixture? |
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| 51459. |
2gm of hydrogen is present in a closed vessel at S.T.P. If the same quantity of another gas 'X' when introduced into the vessel the pressure becomes 1.5 atm. The gas 'X' would be |
| Answer» ANSWER :C | |
| 51460. |
2 g of NaOH per 250 ml of solution is added to a buffer solution of buffer capacity 0.2 . Then the change in pH is |
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Answer» `0.5` |
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| 51461. |
2-Chloro-2-methylpentane on reaction with sodium methoxide in methanol yields : (a)C_2H_5CH_2undersetunderset(CH_3)(|)oversetoverset(CH_3)(|)C-OCH_3 (b)C_2H_5CH_2undersetunderset(CH_3)(|)C=CH_2 (c )C_2H_5CH=undersetunderset(CH_3)(|)C-CH_3 |
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Answer» (a) and (C ) |
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| 51462. |
2- butyne on chlorination gives ……………….. |
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Answer» 1-chlorobutane |
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| 51463. |
2-butyne converts in to dimethyl glyoxal by |
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Answer» BAEYER's REAGENT |
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| 51464. |
2-butene is an example of .............. compound. |
| Answer» SOLUTION :UNSATURATED OPEN CHAIN | |
| 51465. |
2-Butanone is heated with PCl_5 and the product so obtained is heated with alcoholic KOH , the final product obtained is |
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Answer» 1-BUTYNE |
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| 51466. |
2-Bromopentane is treated with alcoholic KOH solution. Whatt will be the major product formed in this reaction and what is the type of elimination called? |
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Answer» Pent-1-ene, `beta`-Elimination<BR>Pent-2-ene, `beta`-elimination |
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| 51467. |
2-Acetoxy benzoic acid is used as an: |
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Answer» antimalarial |
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| 51468. |
2, 3-pentadiene is optically active since it |
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Answer» CONTAINS one chiral carbon atom |
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| 51469. |
1^(ul@) alcohols are poor starting material for synthesis of 1-Alkene. Explain ? |
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Answer» |
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| 51470. |
1^(st) law does not tell about |
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Answer» LAW of conservation of energy |
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| 51471. |
1n which of the following compounds the rule , of octet is not obeyed ? |
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Answer» `H_(2)`O |
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| 51472. |
1mL of unknown solution of H_(2)SO_(4) is diluted upto 100mL and then its 25mL is titrated with 10mL of 0.2 M NaOH. The excess acid required 10mL of 0.1 MBa(OH)_(2) solution. Find molarity of original H_(2)SO_(4) solution. |
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| 51473. |
1m^(3) of C_(2) H_(4) at STP is burnt in oxygen, according to the thermochemical reaction : C_(2)H_(4)(g) + 3O_(2)(g) rarr 2CO_(2)(g) + 2H_(2)O(l) , Delta H = -1410 kJ mol^(-1). Assuming 70% efficients, determine how much of useful heat is evolved in the reaction. |
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Answer» Solution :22.4 L of `C_(2)H_(4)` at STP produces 1410 kJ of energy 1000 L of `C_(2)H_(4)` at STP produces `(1410)/(22.4) xx 1000` (FULL efficiency) At 70% efficiency `= (1410)/(22.4)xx 1000 xx (70)/(100) = 44.02 xx 10^(3) kJ`. |
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| 51474. |
1g Ra^(226) is placed in an evacused tube whose volume is 5 cc, Assuming that each Ra nucleusyieldsfor He atoms which are retainedin the tube, what willbe the pressureof He preoducedat 27^(@)C after the end of 1590 year? (t_(1//2) for Ra is 1590 year) |
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| 51475. |
1g of moist sample of KCI and KCIO_(3) was dissolved in water to make 250mL solution, 25mL of this solution was treatedwith SO_(2) to reducechlorirate to chloride and excess of SO_(2) was removedby boiling. The totalchloride was precipitaed as silver chloride. the weight of precipitate was 0.1435g. In anotherexperiment, 25mL of original solution was heated with 30mL of 0.2N ferrous sulphate solution and unreachedferrous sulphate required 37.5mL of 0.8Nsolution of an oxidant for complete oxidation. Caculate the molar ratio of chlorate int eh given mixture. Fe^(2+) reacts with CIO_(3)^(-) accroding to equaction, CIO_(3)^(-) + 6Fe^(2+) ++ 6H^(+) rarr CI^(-) + 6Fe^(3+) + 3H_(2)O |
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| 51476. |
1g of Mg is burnt in a vessel containing 0.5 g of oxygen. The remaining unreacted is |
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Answer» 0.25g of Mg |
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| 51477. |
1 g of methane diffused in 20 sec. under certain conditions. Under the same conditions sqrt(20)g of a hydrocarbon (A) diffused in 40 sec. A 10 mg of sample of (A) took up 8.40 ml of H_(2) gas measured at 0°C and 760 mm pressure: Identify the incorrect statement. |
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Answer» One of the isomers of (A) exhibits GEOMETRICAL isomerism |
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| 51478. |
1 g of methane diffused in 20 sec. under certain conditions. Under the same conditions sqrt(20)g of a hydrocarbon (A) diffused in 40 sec. A 10 mg of sample of (A) took up 8.40 ml of H_(2) gas measured at 0°C and 760 mm pressure: The number of n. bonds present in the compound A is/are |
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Answer» 2 `10 xx 10^(-3) GM to `8.4 mol of `H_2`. |
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| 51479. |
If one of the open chain isomer of (A) on ozonolysis gives only formaldehyde & glyoxal, then its monocyclic isomer on ozonolysis gives |
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Answer» only glyoxal |
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| 51480. |
1g of a sample of NaOH was dissolved in 50mL 0.33M alkaline solution of KMnO_(4) and refulxed till all the cycanide was converted into OCN^(-). The reaction mixture was cooled and tis 5mLportion was acidified by adding H_(2)SO_(4) in excess an dtehn titrated to end point against 19.0mL of 0.1M FeSO_(4) solutio. Calculate%purity of NaCN sample. |
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| 51481. |
1g hydrogen atoms are excited by radiations. The study of spectrum indicates that 27% of the atoms are in 3rd energy level and 15% of atoms are in 2nd energy level and the rest in the ground state. Ionization potential of hydrogen is 13.6 eV. Calculate (a) number of atoms present in energy level 1st, 2nd and 3rd (b) total energy released in joules when all atoms return to ground state. |
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Answer» SOLUTION :By mole concept, 1g of hydrogen atoms CONTAIN `= 6.02 xx 10^(23)` atoms `:.` 1.8g of hydrogen atoms contain H-atom `= 6.02 xx 10^(23) xx 1.8 = 10.84 xx 10^(23)` Atoms present in 3rd energy level `= (27)/(100) xx 10.84 xx 10^(23) = 292.68 xx 10^(21)` Atoms present in 2nd energy level `= (15)/(100) xx 10.84 xx 10^(23) = 162.6 xx 10^(21)` Atoms present in 1st energy level `= (58)/(100) xx 10.84 xx 10^(23) = 628.72 xx 10^(21)` Ionization potential of H = 13.6 eV means that `E_(1) = -13.6 eV, E_(2) = - (13.6)/(2^(2)) eV, E_(3) = - (13.3)/(3^(2)) eV` Energy released from all atoms when electrons return from 3rd level to 1st level `=(E_(3) - E_(1)) xx 292.68 xx 10^(21) = (-(13.6)/(9) + 13.6) xx 292.68 xx 10^(21) eV` `= 3.537 xx 10^(24) eV` Energy released from all atoms when electrons return from 2nd level to 1st level `= (E_(2) - E_(1)) xx 162.6 xx 10^(21) = ((-13.6)/(4) + 13.6) xx 162.6 xx 10^(21) eV` `= 1.659 xx 10^(24) eV` `:.` Total energy released `= (3.537 + 1.659) xx 10^(24) eV` `= 5.196 xx 10^(24) eV = (5.196 xx 10^(24)) xx (1.602 xx 10^(19)) J` `= 8.3239 xx 10^(5) J = 832.4 kJ` |
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| 51482. |
1g atom of Ra^(226) is placed in an evacuated tube of volume 5 liter. Assuming that each ._(88)Ra^(226) nucleusis an alpha- emitterand all the contentsare present in tube, calculate the total pressure of gases and partial pressure of He collected in tube at 27^(@)after the end of 800 year. Neglect volume occupied by undecayed Ra. |
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| 51483. |
1)C_("Graphite") + O_(2(g)) rarr CO_(2(g)) , DeltaH = -94 K.Cals 2) C_("Diamond") + O_(2(g)) rarr CO_(2(g)) , DeltaH =-94.5 K.Cals From the above data the heat of transition of C_("diamond") rarr C_("Graphite") |
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Answer» `-50 Cal` |
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| 51484. |
.4 sample of H_(2)O_(2) solution containing H_(2)O_(2) by weight requires x ml of KMnO_(4) solution for completed oxidation under acidic condition. The formality of KMnO_(4) solution is |
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Answer» 0.2 M `=(1XX(y//100))/("Eq.wt")xx1000` Meq of `KMnO_(4)=N(y)=(1xx(y//100))/(34//2)xx1000` `=N=(10)/(17)` Molarity = `("Normality")/(5)=(10//17)/(5)=(2)/(17)=0.117M` |
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| 51485. |
18.4 gms of a mixture of calcium carbonate and magnesium carbonate on heating gives 4.0 gms of magnesium oxide. The volume of CO_(2) produced at STP in this process is |
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Answer» `1.12` lit |
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| 51486. |
18.4g of a mixture of CaCO_(3) and MgCO_(3) on heating gives 4.0g of magnesium oxide. The volume of CO_(2) produced at STP in this process is |
| Answer» ANSWER :B | |
| 51487. |
1.84 g of a mixture of CaCO_(3) and MgCO_(3) is strongly heated till no further loss in mass takes place. The residue is found to weigh 0.96 g. Calculate the percentage of each component in the mixture. |
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Answer» Solution :Both `CaCO_(3) and MgCO_(3)` upon HEATING LOSE `CO_(2)` and the mass of residue is that of CaO and MgO. Let us calculate the same from the mixture and quate with the given mass `(0.96g)` Let the mass of `CaCO_(3)` in the mixture =xg `:.` Mass of `MgCO_(3)` in the mixture `(1.84 - x)g` Step I. Calculation of mass of residue (CaO) from x g of `CaCO_(3)` The chemical equation for the REACTION is : `{:(CaCO_(3),overset("Heat")(rarr),CaO+CO_(2)),(40+12+48,,40+16),(=100,,=56g):}` 100 g of `CaCO_(3)` upon heating from CaO (residue) = 56 g `:.` x g of `CaCO_(3)` upon heating form CaO (residue) `= (56)/(100) xx xg` Step II. Calculation of mass of residue (MgO) from `(1-x)`of `MgCO_(3)` `{:(MgCO_(3),overset("Heat")(rarr),MgO+CO_(2)),(24+12+48,,24+16),(=84g,,=40g):}` 84 g of `MgCO_(3)` upon heating from MgO (residue) = 40 g `(1-x)` of `MgCO_(3)` upon heating from MgO (residue) `= (40)/(84) xx(1-x)g` Step III. Calculation of percentage composition of the mixture Total mass of the residue `= [(56)/(100)xxx+(40)/(84)(1-x)]g` But the mass of residue actually formed = 0.96 g EQUATING the two, we get `(56x)/(100)+(40(1-x))/(84)=0.96` `4704x+7360-4000x=0.96xx100xx84=8064` `704x=8064-7360=704,x=(704)/(704)=1` Mass of `CaCO_(3)` in the mixture = 1g Mass of `MgCO_(3)` in the mixture `= 1.84 - 1 = 0.84`g Percentage of `CaCO_(3)` in the mixture `= (1)/(1.84) xx 100 = 54.35 %` Percentage of `MgCO_(3)` in the mixture `= (0.84)/(1.84) xx 100 = 45.65 %` |
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| 51488. |
180ml of hydrocarbon having a molecular weight 16 diffuses in 1.5 min. Under similar conditions time taken by 120ml of So, to diffuse is |
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Answer» 2 min `implies t = (120 XX 2)/(180) xx 1.5 = 2 ` min. |
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| 51489. |
180 mL of a hydrocarbon diffuse through a porous membrane in 15 minutes, while 120 mL of SO_2 under identical conditions diffuse in 20 minutes. What is the molecular mass of the hydrocarbon ? |
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Answer» SOLUTION :Rate of diffusion of hydrocarbon `(r_(1)) = 180//15 = 12` mL/MIN Rate of diffusion of `SO_(2)(r_(2)) = 120/20 = 6 mL`/min Molecular mass of `SO_(2) (M_(2)) = 32 + (2 xx 16) = 64` According to Graham.s LAW of diffusion, `r_(1)/r_(2) = sqrt(M_(2)/M_(1))` Substituting the values, we get `12/6 = sqrt(64/M_(1))` or `M_(1) = (6 xx 6 xx 64)/(12 xx 12) = 16` Hence, the molecular mass of the hydrocarbon is 16. |
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| 51490. |
18.0 g of water completely vaporises at 100°C and 1 bar pressure and the enthalpy change in the process is 40. 79 "kJ mol"^(-1). What will be the enthalpy change for vapourising two moles of water under the same conditions ? What is the standard enthalpy of vapourisation for water ? |
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Answer» SOLUTION :Quantity of water = 18.0 g, pressure 1 bar As we know that, `18.0 g H_(2) O = 1 "MOLE" H_(2) O` ENTHALPY change for vapourising l mole of `H_(2) O = 40.79 "kJ mol"^(-1)` `therefore` Enthalpy change for vapourising 2 moles of `H_(2) O = 2 xx 40.79 "kJ" = 81.358 "kJ"` Standard enthalpy of vaporisation at 100°C and 1 bar pressure, `Delta_("vap") H^(@) = + 40.79 "kJ mol"^(-1)` |
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| 51491. |
18.0 g of water completely vapourises at 100^(@)C and 1 bar pressure and the enthalpy change for the process is 40.79 kJ mol^(-1). (i) What will be the enthalpy change for vapourising 2 moles of water under the same conditions? (ii) What is the standard enthalpy of vapourisation for water? |
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Answer» SOLUTION :18.0 of water = 1 MOL Standard enthalpy of VAPORISATION at `100^(@)C` and 1 bar PRESSURE = `40.79 kJ"mol"^(-1)`. Enthalpy change in vaporisation of 2 mol of water `= 2 XX 40.79 = 81.58` kJ. |
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| 51492. |
18.0 g of water completely vaporises at 100^(@)C and 1 bar pressure and the enthalpy change in the process is40.79 kJ mol^(-1). What will be the enthalpychange for vaporising two moles of water under the same conditions ? What is the standard enthalpy of vaporisation for water ? |
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Answer» Solution :`18.0` g of WATER `=` 1 mole `:. ` Standard ENTHALPY of vaporisation at`100^(@)C` and 1 bar pressure `=40.79 kJ MOL^(-1)` Enthalpy change in vaporisationof 2 moles of water `= 2 xx 40.79 kJ = 81. 58 kJ` |
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| 51493. |
1.80 g of impure sample of oxalate was dissolved in water and the solution made to 250 mL. On titration 20 mL of this solution required 30 mL of M/50 KMnO_4 solution . Calculated the percentage purity of the sample. |
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Answer» Solution :The BALANCED chemical equation is : `2MnO_4^(-)+5C_2O_4^(2-)+16H^(+)rarr2Mn^(2+)+10CO_2+8H_2O` Applying morality equation , `((M_1V_1)/n_1)_(KMnO_4)-=((M_2V_2)/n_1)_(C_2O_4^(2-))` `1/50xx30/2-=(M_2xx20)/5` `M_2=(30xx5)/(50xx2xx20)=0.075M` MOLECULAR wt. of `C_2O_4^(2-) =88` Wt of `C_2O_4^(2-) = 0.075 xx88=6.6g` AMOUNT of `C_2O_4^(2-) ` in 250 mL `=(6.6)/1000xx250=1.65g` % Purity `=(1.65)/(1.80)xx100=91.7%` |
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| 51494. |
1.80 g of a metal oxide required 833 mL of hydrogen at NTP to be reduced to its metal. Find the equivalent weights of the oxide and the metal. |
| Answer» SOLUTION :24.2, 16.2 | |
| 51495. |
18 gms of glucose contains |
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Answer» 0.6 gram-atoms of carbon 180 GRAMS glucose - `6.023xx10^(23)` MOLECULES - 72 grams carbons - 12 grams hydrogen |
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| 51496. |
18 g of water contain: |
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Answer» 1 g ATOM of hydrogen |
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| 51497. |
18 g of glucose is dissolved in 90 g of water. The relative lowering of vapour pressure is equal to …………. |
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Answer» <P> Solution :`0.1 ``(P^(@) -P)/(P ^(@)) = x _(2) impliesx_(2) =` No. of moles of GLUCOSE `= (18)/(180) =0.1` `therefore (P^(@) -P)/(P^(@)) =0.1` |
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| 51498. |
18 C-H and 7 C-C sigma bonds are in |
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Answer» Cyclohexane |
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| 51499. |
1.78N ofH_(2)O_(2) solution is : |
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Answer» 10 VOLUMES of `H_(2)O_(2)` |
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| 51500. |
1.725 g of a metal carbonate is mixed with 300 mL of (N)/(10)HCl. 10 mL " of" (N)/(2) sodium hydroxide were required to neutralise excess of the acid. Calculate the equivalent mass of the metal carbonate. |
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Answer» Solution :`10 mL "of" (N)/(2) NaOH` solution `=10 mL " of" (N)/(2)HCL` solution `-=50 mL " of" (N)/(10)HCl` solution Volume of `(N)/(10)HCl` used for neutralisation =300-50=250 mL 250 mL of `(N)/(10)HCl-=250 mL " of" (N)/(10)` METAL carbonate solution Let the equivalent mass of metal carbonate be E. Mass of metal carbonate present in solution `=(NxxExxV)/(1000)=1.725` `=(1xxExx250)/(10xx1000)=1.725` `=(E )/(40)=1.725` `E=40xx1.725=69` |
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