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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.
| 20901. |
Why are colloids purified? |
| Answer» Solution :The COLLOIDAL SOLUTIONS DUE to their different methods of PREPARATION may contain impurities. If they are not removed, they may destablise and precipitate the colloidal solution. | |
| 20902. |
The standard electrode potential of SHE at 298 K is …………… . |
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Answer» `0.05 V ` |
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| 20903. |
To produce 160 g of oxygen, the number of mole of water required to be electrolysed is : |
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Answer» `2.5` |
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| 20904. |
Which of the following metallurgical process does not involve heating? |
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Answer» SMELTING |
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| 20905. |
whichoneof thefollowingstatementsforthe orderof a ractionis incorrect ? |
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Answer» order is notinfluencedbystoichliometric coefficientof thereactants |
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| 20906. |
Write the role of ‘CO’ in the purification of nickel. |
| Answer» Solution :To produce a volatile complex, which DECOMPOSES on further HEATING to GIVE pure nickel. | |
| 20907. |
Which type of isomerism is possible in [Co(NH_(3))_(5)(No_(2))]^(2+) ? |
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Answer» LIGAND isomerism |
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| 20908. |
Which forces are not responsible for the stability of the tertiary structure of proteins ? |
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Answer» Disulphide linkages |
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| 20909. |
What is molecularity of a reaction ? |
| Answer» Solution :The number of reacting SPECIES (atoms, IONS or molecules) TAKING part in an elementary reaction which must collide SIMULTANEOUSLY in order to BRING about a chemical reaction is called molecularity of areaction. | |
| 20910. |
Ziegler-Natta catalyst is |
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Answer» Triethylaluminium and TITANIUM trichloride |
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| 20911. |
Two flasks A and B of 1L each are filled with O_(2) and SO_(2) gas at 27^(@)C and 1 atm pressure. The flasks will contain . |
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Answer» same number of atoms |
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| 20912. |
Which one of the following is/are suboxides? |
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Answer» `CrO_(5)` |
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| 20913. |
Which oxide of nitrogen is neutral ? |
| Answer» SOLUTION :`N_2O,NO` | |
| 20914. |
Which one is not called an anode reaction from the following |
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Answer» `Cl^(-)to(1)/(2)Cl_(2)+E^(-)`  . It shows reduction REACTION.
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| 20916. |
Which of the following is paramagnetic in nature? |
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Answer» `[Zn(NH_(3))_(4)]^(2+)` |
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| 20917. |
Which one of the following is not a protein ? |
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Answer» Wool |
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| 20918. |
When pyrolusite is fused with KOH the compound formed is ____ |
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Answer» `K_2MnO_4` |
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| 20919. |
Write the general formula of diazonium salt |
| Answer» SOLUTION :`RN_(2)^(+) X^(-) "" `R= ARYL group OR `ArN_2^(+)X^(-)` | |
| 20920. |
Which of the following ions show higher spin only magnetic moment value? |
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Answer» `Ti^(3+)` `Mn^(2+)=[Ar] 3d^(5), (t_(2G)^(3)e_(g)^(2))` `Fe^(2+)=[Ar]3d^(6)(t_(2g)^(4)e_(2g)^(2))` `Co^(3+)=[Ar] 3d^(6)(t_(2g)^(6)e_(g)^(0))` Crystal field SPLITTING energy (CFSE) is high in `Co^(3+)`, thus electrons pair up in `t_(2g)`. Hence, only `Fe^(2+)` and `Mn^(2+)` show HIGHER spin magnetic moment value. |
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| 20921. |
Write the method to produce copper matte from copper pyrites. |
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Answer» |
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| 20922. |
Which of the following solutions can act as buffer |
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Answer» 0.1 molar aq. NaCl |
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| 20923. |
Writethe Nernstequationfor followingcell : Sn(s) |Sn^(2+) ||H^+|H_2 (g)(1 "bar" )| Pt (s) |
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Answer» Solution :The cellreactionis `SN +2H^+to Sn^(2+)+H_2` `n=2` ` E_("cell") =E_("cell")^@ +(2.303 RT ) /( nF )LOG ([H^+]^2)/([Sn^(2+)])` `or E_("cell ")=E_("cell ")^(@)+(0.591 )/(n ) log ([H^+ ]^2)/((Sn^(2+))` |
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| 20924. |
Which of the following gives condensation with hydroxyl amine but does not undergo self condensation ? |
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Answer» Methanal  Methanal dows not contain `alpha-`HYDROGEN atom, hence it does not UNDERGO self condensation. |
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| 20925. |
Which of the following is a linear polymer ? |
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Answer» Nylon |
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| 20926. |
Which of the following polymers contain1,3,-butadiene as one of the monomers? |
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Answer» Nylon-6,6` .(d)`SBR`(refers to styrene butadienerubber) BUTYL rubber also refers to butadiene. (d)Nitrile rubber refers to`Bune-N` |
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| 20927. |
The value of osmotic pressure of a 0.2 M aqueous solution at 293 K is |
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Answer» 8.4 ATM |
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| 20928. |
Which of the following properties of the elements of group II (alkali earth metals) increase (s) with increasing atomic number? |
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Answer» STABILITY of carbonate |
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| 20929. |
Which is not permissible subshell ? |
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Answer» 2d |
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| 20930. |
Which of the following compounds is most acidic ? |
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Answer» `H_(2)O` |
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| 20931. |
Which ofthefollowingcompoundis usedas arefrigerant ? |
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Answer» ` C C l_4` |
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| 20932. |
What is the role of diffusion in heterogeneous catalysis ? |
| Answer» Solution :The REACTANTS are MADE to diffuse on the surface of the catalyst for the ADSORPTION. After the adsorption TAKES place, the PRODUCTS are formed which are diffused away from the catalyst surface. | |
| 20933. |
Tollen's reagent is : |
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Answer» AMMONIACAL CUPROUS chloride |
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| 20934. |
Write the equation for i) The action of SO_(2) with chlorine in the presence of charcoal ii) The actionof SO_(3) with concentrated sulphuric acid iii) The action of ozone with lead sulphide. |
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Answer» Solution :(i) `SO_(2)+Cl_(2)RARR SO_(2)Cl_(2)` (ii) `SO_(3)+H_(2)SO_(4)rarr H_(2)S_(2)O_(7)` (iii) `4O_(3)+PbSrarr PbSO_(4)+4O_(2)` |
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| 20935. |
Which statement is true about spontaneous cell reaction in galvanic cell: |
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Answer» `E_(cell)^@ gt 0,Delta G^@ LT 0,Quotient Q lt K_c` |
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| 20936. |
What are F-centres ? |
| Answer» Solution :The FREE electrons in a crystal present in the HOLES caused by anion vacancies which impart COLOUR to a crystal are called F-centres. | |
| 20937. |
What is the coordination number of atoms in (i) Cubic closed packed structure (ii) Body centred cubic structure? |
| Answer» SOLUTION :(i) 12 (II) 8. | |
| 20938. |
What are alcohols, phenols and ethers ? State the various applications of these compounds in day-to-day life ? |
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Answer» Solution :`to` The alcohols and phenols are formed by the replacement of hydrogen atom in an aliphatic and aromatic hydrocarbon respectively. The ethers are formed by the replacement of the hydrogen atom in hydrocarbon by alkoxy or aryloxy groups. The ethers may also VISUALIZE as the replacement of hydrogen of -OH group of alcohol or phenol by alkyl or aryl group. `to` The alcohols CONTAIN one or more than one -OH groups BONDED directly to carbon atom(s) of an aliphatic system `(CH_(3)OH)` whereas phenol contains -OH group(s) bonded directly to the `sp^(2)` carbon of an aromatic system (`C_(6)H_(5)OH`). `to` Applications : Ethanol is used for polishing of a wooden furniture. It is called ordinary spirit. The sugar we eat, the cotton used in fabrics, the paper used for WRITING, are all made of compounds containing -OH groups. |
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| 20939. |
When n-hexane/n-heptane is passed through Cr_2O_3 supported over alumina at 600^@Cgives: |
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Answer» Hexane |
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| 20940. |
Which of the following is dextron , |
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Answer» `[-CH_2-overset(O)overset(||)C-]_n` |
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| 20942. |
Which of the folowing acids shows sterioisomerism |
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Answer» Formic acid |
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| 20943. |
Which of the following compounds, on reaction with NaOH and Na_(2)O_(2), gives yellow colour |
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Answer» `Zn(OH)_(2)` `Cr(OH)_(3)+NaOH+Na_(2)O_(2) to Na_(2)CrO_(4)+2H_(2)O` |
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| 20944. |
Write one similarity between physisorption and chemisorptions. |
| Answer» Solution :Both physisoption and CHEMISORPTION INCREASE with increase in the surface AREA of the ADSORBENTS. | |
| 20945. |
What is meant by the following terms? Give an example of the reaction in each case. (i) Cyanohydrin "" (ii) Acetal (iii) Semicarbazone "" (iv) Aldol (v) Hemiacetal "" (vi) Oxime (vii) Ketal "" (viii) Imine (ix) 2, 4-DNP-derivative "" (x) Schiff's base . |
Answer» Solution :Compounds possessing hydroxyl and cyano groups on the same carbon atom are called cyanohydrins. These are produced by addition of HCN to aldehydes or ketones in weakly basic medium  Cyanohydrins are useful synthetic reagents, they are used to prepare a-hydroxyacids. For example,  (ii) Compounds in which two alkoxy groups are present on the terminal carbon atom are called acetals. These are produced by the action of an aldehyde with two equivalents of a monohydric alcohol in presence of dry HCl gas.  They are easily hydrolysed by dilute mineral acid to regenerate the original aldehydes. Therefore, they are used for the protection of aldehyde group in ORGANIC synthesis and for the purification of aldehydes. (iii) Semicarbazones are derivatives of aldehydes or ketones and are produced by the action of semicarbazide in weakly acidic medium,  These are used for identification and characterisation of aldehydes and ketones. (iv) Aldols are `beta`-hydroxyaldehydes or ketones. They are produced by the condensation of two molecules of the same or one molecule each of two DIFFERENT aldehydes or ketones in presence of a dilute aqueous base. For example,  (v) Alcohols containing on alkoxy group are called hemiacetals. These are produced by addition of one molecule of a monohydric alcohol to an aldehyde in presence of dry HCl gas.  (VI) When aldehydes or ketones react with hydroxylamine in weakly acidic medium, oximes are formed.  (VII) Ketals are produced when a ketone is heated with ethylene glycol in presence of dry HCI gas or p-toluenesulphonic acid (PTS). It has a cyclic structure.  These are easily hydrolysed by dilute mineral acids to regenerate the original ketones. Therefore, ketals are used for protection of keto groups in organic synthesis. (viii) Compound containg -CH=N-group are called imines. These are produced when aldehydes and ketones reacts with ammonia and its derivatives.  `Z = H, Alkyl , aryl, -NH, -OH, -NHC_6H_5, -NHCONH_2, ` etc. (ix) Aldehydes or ketones react with 2,4-dinitrophenylhydrazine in weakly acidic medium to produce 2, 4-DNP derivative. 2,4-Dinitrophenyl Acetone 2,4-Dinitrophenylhydrazone hydrazine (2.4-DNP derivative) 2,4-DNP derivatives are used for identification and characterisation of aldehydes and ketones. (x) Aldehydes and ketones react with primary aliphatic or aromatic amines in presence of TRACE of an acid to form azomethines or Schiff.s bases. In principle, Schiff.s bases are imines. 
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| 20946. |
Which of the following compounds do not give free halogen acid (Hydra acid) on hydrolysis with excess water as a final product? |
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Answer» `NCl_(3)` |
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| 20947. |
What are homoleptic complexes? |
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Answer» Solution :Complexes in which a metal is BOUND to only ONE KIND of donor group are called homoleptic complexes. e.g., `[Co(NH_3)_6]^(3+)`. OR Any SUITABLE statement |
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| 20948. |
The standard reduction potential at 298 K for the following half cell reactions are given below Zn^(2+)(aq)+2e^(-) to Zn(s) "" E^(@)=-0.762V Cr^(3+)(aq)+3e^(-)toCr(s) ""E^(@)=-0.740V2H^(+)(aq)+2e^(-) toH_(2)(g) "" E^(@)=0.0VFe^(3+)(aq)+e^(-) toFe^(2+)(aq) "" E^(@)=0.77V.Which is the strongest reducing agent ? |
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Answer» Zn (s) |
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| 20949. |
Which of the following statement (s) is/are correct when a mixture of NaCl and K_(2)Cr_(2)O_(7) si gently warmed with conc. H_(2)SO_(4)? (I)A deep red vapour is evoleved. ltbr4gt (II) The vapour when passes into NaOH solutiongives a yellow solution of Na_(2)CrO_(4). (III) Chomyl chloride is formed. Choose the coorect option. |
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Answer» I and II |
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| 20950. |
Which of thefollowingreactionor reactionsequencecan be usedto prepareepoxides ? |
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Answer»
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