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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.
| 87451. |
A small hole is pricked in a container containing a mixture of CH_(4) and O_(2) and placed in vacuum. What should be the molar ratio of methane to oxygen in the contianer when the two gases are effusing out in the ratio of 2:1 |
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Answer» `SQRT(2) : 1` |
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| 87452. |
A small amount of silica gel and a small amount of anhydrous calcium chlo-ride are placed separately in two beakers containing water vapour. Name the phenomenon that takes place in both the beakers. |
| Answer» SOLUTION :Silica GEL: ADSORPTION, Anhydeous `CaCl_(2)` : ABSORPTION, as it FROMS `Ca-Cl_(2). 2H_(2)O` | |
| 87453. |
A small amount of ethanol is usually added to chloroform bottles? Why. |
Answer» Solution :ETHANOL combines with the POISONOUS phosgene GAS which may have formed during storage and converts it into HARMLESS (non-toxic) diethyl CARBONATE. 
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| 87454. |
A small amount of alcohol is usually added to CHCl_3 from ethanol and bleaching powder the latter provides: |
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Answer» |
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| 87455. |
A smallamountof anon-valatile , non-electroytesoluteis dissolvedin 56.8 cm^(3)ofbenzene( density0.89g//cm^(3)) .Atroomtemperature,the vapourpressureof thissolutionis 98.9mm Hg, whilethatof benzeneis100 mm.Hg, Findthe molariltyof thissolution |
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Answer» `0.144` |
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| 87456. |
A slope of a graph In [A] versus 't' for a first order is -5 xx 10^(-4)s^(-1). The rate constant for the reaction will be. |
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Answer» `10 xx 10^(-3)s^(-1)` In `[A] = - kt + In [A]_0` hence SLOPE = - k `:. K = -"slope"` `=-(-5 xx 10^(-3))s^(-1)` ` =+5 xx 10^(-3)s^(-1)` |
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| 87457. |
A six coordination complex of formula CrCl_(3)*6H_(2)O has green colour. A 0.1 M solution of the complex when treated with excess of AgNO_(3) gas 28.7g of white precipitate. The formula of the complex would be: |
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Answer» `[CR(H_(2)O)_(6)]Cl_(3)` |
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| 87458. |
A single electron atom has a nuclear charge +Ze where Z is the atomic number and ‘e’ is the electronic charge. It requires 47.2ev to excite the electron from 2 ^(nd) Bohr's orbit to 3 ^(rd) Bohr's orbit from above given data solve the following question : In thehydrogen atom, if the reference level of potential energy is assumed to be zero at the ground state level. Choose thencorrect statement. |
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Answer» The total ENERGY of the shell increases with INCREASE in the value of n |
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| 87459. |
A single electron system has ionization energy 20902.2 kJ//mole. Find the number of protons in the nucleus of the system. |
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Answer» |
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| 87460. |
A single substance that exists in two or more forms is called |
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Answer» polymorphous |
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| 87461. |
(A) Single crystals are formed when the process of crystallization is rapid (R) Single larger crystals have less defects compared to small crystals. |
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Answer» Both (A) and (R) are true and (R) is the CORRECT explanation of (A) |
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| 87462. |
A single compound of the structure OHC - CH_(2) -overset(CH_(3))overset(|)(CH) - CH_(2) -overset(CH_(3))overset(|)(C)= O is obtainable from ozonolysis of which of the following cyclic comounds ? |
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| 87463. |
A single compound of the structure is obtainable from ozonolysis of which of the following cyclic compounds ? |
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Answer»
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| 87464. |
A simplest aromatic hydrocarbon (A) reacts with methyl chloride in the presence of AICI_3gives (B) C_7H_8Compound (B) reacts with Br, along with light gives ( C) of molecular formula C_7H_7Br( C) reacts with alcohol KCN gives (D) (C_8H_7N)(D) on acid hydrolysis gives (E) of formula C_8H_8O_2 . Identify A,B,C,D,E and explain the reactions involved. |
Answer» SOLUTION :
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| 87465. |
A simplest aromatic hydrocarbon (A) of formula C_6H_6reacts with Bromine to gives (B) of molecular formula C_6 H_5 Br . (B) on treatment with magnesium metal in the presence of dry ether gives (C).(C) on reaction with formaldehyde followed by acid hydrolysis gives (D) of formula C_7H_8O . Identify A,B,C,D and explain the reaction involved. |
Answer» Solution :(i) From the MOLECULAR formula (A) is identified as BENZENE `C_6H_6` . Benzene reacts with BROMINE to GIVE bromobenzene as (B) 
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| 87466. |
A simple method to remove peroxides from ehters is to treat them with an aqueous solution of |
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Answer» `FeSO_4`<BR>KCNS |
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| 87467. |
A simple mehtod to remove peroxide form ehters is to treat them with an aqueous solution |
| Answer» Solution :NA | |
| 87468. |
A simple cubic lattice consists of eight identical spheres of radius R in contact, placed at the corners of a cube. What is the volume of the cubical box that will just enclose these eight spheres and what fraction of this volume is actually occupied by the spheres? |
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| 87469. |
A simole oxide of carbon and that another non-metal have the same Cp/Cv ratio but a difference of 2 in their molecular weights. The other non-metal could be? |
| Answer» Solution :`N_2` is less reactive at room temperature due to presence of TRIPLE bond between two N ATOMS `NcongN` HENCE bond Dissociation energy `N_2` is bery HIGH. | |
| 87470. |
A similarity between optical and geometrical isomerism is that: |
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Answer» each FORMS equal number of ISOMERS for a GIVEN compound |
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| 87471. |
A similarity between optical and geometrical isomerism is that : |
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Answer» each FORM equal number of ISOMERS for a given compound |
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| 87472. |
A silver salt of fatty acid on heating with an alkyl halide gives: |
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Answer» ETHER |
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| 87473. |
A silver salt of fatty acid on heating with alkyl halide gives : |
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Answer» ETHER |
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| 87474. |
(A) Silver. Gold and platinum are precious metals. (R) Silver glod and platinum are good conductors. |
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Answer» Both (A) and (R) are TRUE and (R) is the CORRECT EXPLANATION of (A) |
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| 87475. |
(A): Silver cyanide complex is treated with zinc to precipitate silver metal (R): Zinc cyanide complex is more stable than silver cyanide complex. |
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Answer» Both A & R are TRUE, R is the CORRECT EXPLANATION of A |
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| 87476. |
A silver cup is plated with silver by passing 965 coulombs of electricity . The amount of Ag deposited is |
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Answer» 1.0787 gm |
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| 87477. |
A silver cup is plated with silver by passing 965 coulomb of electricity . The amount of Ag deposited is : |
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Answer» `1.08g` |
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| 87478. |
A silicon solar battery makes use of- |
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Answer» n-Type SEMICONDUCTOR |
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| 87479. |
A : Silicon is insulator at 0 K but semiconductor at room temperature. R : Conductivity of silicon at room temperature is due to electronic defect. |
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Answer» If both Assertion & REASON are TRUE and the reason is the correct explanation of the assertion then mark (1) |
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| 87480. |
A signature, written in carbon pencil weighs 1 mg. what is the number of carbon atoms present in the signature? |
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Answer» `5.02xx10^(23)` `because` 12g carbon CONTAINS=`6.023xx10^(23)` carbon atoms `therefore1xx10^(-3)` g carbon contains `=(6.023xx10^(23))/(12)xx1xx10^(-3)` `=0.502xx10^(20)` carbon atoms. |
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| 87481. |
A sigma bond is formed by the overlapping of |
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Answer» Only s-s ORBITALS |
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| 87482. |
Show that for a first order reaction, t_(99.9%)=10t_(1//2). |
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Answer» Solution :For first order reaction `t=(2.303)/(K)log""([R]_(0))/([R])` The TIME required for `99.9%` completion is `t_(99.9%)=(2.303)/(K)log""(100)/(100-99.9)` `=(2.303)/(K)log""(100)/(0.1)` `=(2.303)/(K)log 1000` `=(2.303)/(K)LOG10^(3)""[logm^(n)=n log m]` `t_(99.9%)=(3xx2.303)/(K)rArr (6.909)/(K)"….(1)"` For the first order reaction line required line required to complete `50%` is `t_(1//2)=(0.693)/(K)"…(2)"` `(eq(1))/(eq(2))` `(t_(99.9%))/(t_(1//2))=(((9.909)K))/((0.909)/(K))` `rArr (6.909)/(K)xx(K)/(0.693)` `(t_(99.9%))/(t_(1//2))=10""rArr""t_(199.9%=10t_(1//2)` |
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| 87483. |
(a) SF_6is not easily hydrolysed. Explain. (b) Ozone is used for purifying air in crowded places such as cinema halls, tunnels, etc. Explain. (c) Why oxide ion is called hard ion ? Explain. |
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Answer» Solution :(a)` SF_6`is chemically inert and THEREFORE, does not GET hydrolysed. Its inert nature is due to the presence of stearically protected sulphur atom which does not allow thermodynamically favourable HYDROLYSIS reaction. (B) Ozone is an endothermic compound and easily decomposes to produce `O_2`as: ` 2O_3 to 3O_2` Therefore, it purifies crowded places. (c) Oxide ION is very small in size and therefore, it cannot be easily polarized. Hence, it is called hard ion. |
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| 87484. |
A set of reagents (1 to 8) are successively rected with the following compound 1. NaHCO_(3) 2. 2,4, DNP 3. Na metal 4. AgNO_(3)+NH_(4)OH 5. Fehling's solution 6. Cu_(2)+NH_(4)OH 7. Br_(2)//H_(2)O 8. NaNO_(2)+HCl THe reagents which give positive test with the given compound are: |
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Answer» 1,2,3,4,5, |
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| 87485. |
A set of reagent (1 to 8) are successively reacted with the following compound 1.NaHCO_3 , 2. 2,4-DNP, 3. Na metal 4. AgNO_3+NH_4OH , 5.Fehling's solution , 6. Cu_2Cl_2+NH_4OH 7.Br_2//H_2O , 8.NaNO_2+HCl The reagent which give positive test with the given compound are : |
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Answer» 1,2,3,4,5 `therefore` Reagents 1 and 8 will fall to GIVE TEST |
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| 87486. |
A set of reaction yielded a product D. C_(2)H_(5) COOH overset(SOCl_(2)) to A underset("unhy."AlCl_(3))overset(C_(6)H_(6)) to B overset(NCN) to C overset(H_(3)O^(+)) to D |
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Answer»
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| 87487. |
A set of compounds in which the reactivity of halogen atom is in ascending order is |
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Answer» CHLOROBENZENE `LT` VINYL CHLORIDE `lt` ETHYL chloride |
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| 87488. |
A set of compounds in which reactivity of halogen atom in their ascending order is …….. |
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Answer» Chlorobenzene, Vinyl CHLORIDE, CHLOROETHANE |
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| 87489. |
A secondary cell is one |
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Answer» can be recharged |
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| 87490. |
A series of lines in the specturm of atomic hydrogen lies at wavelengths 656.46, 482.7, 434.17, 410.29nm. What is the wavelength of next line in this series. |
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Answer» |
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| 87491. |
A sequential reaction may be performed as represented blow: (##MBD_HKR_CHE_XII_P02_C12_E07_506_Q01##) |
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Answer» BROMINE alone |
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| 87492. |
A sequential reaction may be performed as represented blow: '(##MBD_HKR_CHE_XII_P02_C12_E07_506_Q01##)' |
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Answer» BROMINE alone |
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| 87493. |
A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid ? |
| Answer» ANSWER :A | |
| 87494. |
A section of the priodic table is given below withelements A,B and X,Y in two grops. Which of the bond given below is the least polar? |
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Answer» AX |
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| 87495. |
A: Secondary amines and phenols undergo Liebermann nitroso reaction. R: Secondary amines are move basic than primary amines. |
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Answer» Both A and R are true and R is CORRECT EXPLANATION of A |
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| 87496. |
A secondary amine is |
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Answer» An organic compound with two`-NH_(2)` GROUPS |
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| 87497. |
A secondaryamineis |
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Answer» a compoundwithtwo CARON atomsand an`-NH_(2)`group |
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| 87498. |
A secondary amine can be obtained by the reduction of |
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Answer»
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| 87499. |
A secondary amine is : |
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Answer» A compound with two -`NH_2` groups |
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| 87500. |
A secondary (2^@) carbon atom is one that is joined to: |
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Answer» 1-alkyl group |
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