Saved Bookmarks
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.
| 16901. |
Whichmethodofpurificationisrepresentedbythefollowingequation ?Ti(s)+2 I _ 2 (g)overset (523 K) toTiI_4(g) overset (1700 K) toTi(s) +2 I_2 (g) |
|
Answer» CUPELLATION |
|
| 16903. |
Which reagent is used to differentiate between aldehyde and ketone ? |
|
Answer» FEHLING's solution |
|
| 16904. |
When an alkyl halide is heated with dry Ag_2O,it produces |
|
Answer» ester |
|
| 16906. |
Which of the following is NOT a sex hormone ? |
|
Answer» ESTROGEN |
|
| 16907. |
When phenol reacts with phthalic anhydride in presence of H_2SO_4and heated and hot reaction mixture is poured inNaOH solution. The product formed is |
|
Answer» Alizarin |
|
| 16908. |
What is ammonolysis ? Give its application. |
|
Answer» Solution :It is the replacement of either halogen ATOM of alkyl halides or HYDROXYL group in alcohols by amino group. Reagent USED for this purpose is alcoholic ammonia. Example: `R-X+NH_3 RARR R-NH_2 + HX` `R-OH + NH_3 overset(Al_2O_3)underset(360^@C)rarr RNH_2+H_2O` Application: It is used for the preparation of primary, secondary, tertiary amines from haloalkanes. |
|
| 16909. |
What is the rate of the reaction for2AtoB |
|
Answer» `-(d[A])/(DT)` |
|
| 16910. |
When sodium acetate is added to acetic acid, the degree of ionisation of acetic acid |
|
Answer» increases |
|
| 16911. |
While antacids and antiallergic drugs interfere with the function of histamines, why do these not interfere with the function of each other ? |
| Answer» Solution :Drugs designed to cure some AILMENT in one organ in the body do not affect the other because they work on different receptors. For example, secretion of histamine causes allergy. It ALSO causes acidity due to release of hydrochloric ACID in the stomach. Since antiallergic and antacids drugs work on different receptors, THEREFORE, antihistamines RELIEVE allergy while antacid remove acidity | |
| 16912. |
X' is an optically active alkane having lowest molecular mass, Predict the structure of the major product obtained on monochlorination of 'X'. |
|
Answer» `CH_(3)-CH_(2)-CH_(2)-UNDERSET(Cl)underset(|)overset(CH_(3))overset(|)C-CH_(2)-CH_(3)` |
|
| 16913. |
Which one of the following properties is not shown by NO ? |
|
Answer» It combines with OXYGEN to form NITROGEN dioxide. |
|
| 16914. |
Vegetable colouring matter in presence of moisture is bleached by SO_2 due to: |
|
Answer» Oxidation |
|
| 16916. |
VSEPR theory does bot state : |
|
Answer» the order of repulaion between different pair of elctrons is `lp - lp GT lp - bp gt bp = bp` (lp = lone pair ELECTRONS, bp = bond pair electrons) |
|
| 16917. |
Which of the following acids is (are) monobasic? |
|
Answer» <P>`H_(3)PO_(2)` |
|
| 16918. |
What is the maximumvolumeof waterrequired to dissolve1 g of calciumsulphate at298 K . For calciumsulphate K_(sp) = 9.1 10^(-5) |
|
Answer» Solution :`CaSO_(4) (aq) hArr CA^(2+)(aq) +SO_(4)^(2-) (aq)` If S ISTHE solubilityof `CaSO_(4)` in moles `L^(-1)` `K_(sp) = [Ca^(2+)] = [SO_(4)^(2-)] = S^(2)` ` :. S = sqrt(K_(sp)) = sqrt(9.1 xx10^(-6))` ` = 3.02 xx10^(-3) "ML"^(-1)` . ` = 3.02 xx10^(-3) xx136 "gmL"^(-1)` ` = 0.411 "gL"^(-1)` For dissolving `1gCaSO_(4)`water required = `1/(0.41) L = 2.431 ` |
|
| 16919. |
Which of the following does not contain peroxy linkage? |
| Answer» Answer :B | |
| 16920. |
Which of the following will not enhance nutritional value of food ? |
|
Answer» Minerals |
|
| 16921. |
Which energy is lowered when we use a catalyst in a chemical reaction ? |
| Answer» SOLUTION :ACTIVATION | |
| 16922. |
What are the advantages of Brownian movement? |
|
Answer» Solution :Brownian movement enables us, (i) to calculate Avogadro number. (ii) to confirm kinetic theory which considers the ceaseless rapid movement of molecules that increases with INCREASE in TEMPERATURE. (iii) to understand the stability of colloids: As the particles are in continuous rapid movement they do not come close and hence not get condensed. (IV) That is Brownian movement does not allow the particles to be acted on by force of gravity. |
|
| 16923. |
Write the formula for the following coordination compounds. (a) potasiumhexacyanidoferrate (II) (b) petacarbonyliron (0) (c ) pentaamminenitrito - k -N-cobalt (III) ion (d) hexaamminecobalt (III) sulphate (e ) sodiumtetrafluoridhydroxidochromate (III) |
|
Answer» Solution :`(a)` potasiumhexacyanidoferrate (II)`=K_(4)[Fe(CN)_(6)]` `(b)` petacarbonyliron (0) `=[Fe(CO)_(5)]` `(c )` pentaamminenitrito - k -N-cobalt (III) ion `=[Co(NH_(3))_(5)NO_(2)]^(2+)` `(d)` HEXAAMMINECOBALT (III) sulphate `=[Co(CN)_(6)]_(2)(SO_(4))_(3)` `(e )` sodiumtetrafluoridhydroxidochromate (III) `=Na_(3)[CrF_(4)(OH)_(2)]` |
|
| 16924. |
The vapour pressures of benzene and toluene at 20^(@)C are 75mmHg and 22mmHg respectively. 23.4g of benzene and 64.4 g of toluene are mixed. If the two form an ideal solution, calculate the mole fraction of benzene in the vapour phase if the vapours are in equilibrium with the liquid mixture at the same temperature. |
|
Answer» Solution :No.of MOLES of BENZENE in liquid `=(23.4)/(78)=0.3` `(C_(6)H_(6)=78)` No. of moles of toluene in liquid `=(64.4)/(92)=0.7`. `(C_(6)H_(5)CH_(3)=92)` `:.` mole fraction of benzene `=(0.3)/(0.3+0.7)=0.3` `:.` mole fraction of toluene `=(0.7)/(0.3+0.7)=0.7` Partial pressure of benzene `=75xx0.3=22.5` Partial pressure of toluene `=22xx0.7=15.4`..........(Eqn.2) TOTAL pressure `=22.5+15.4=37.9mm` Mole fraction of benzene in vapour phase `=("partial pressure")/("total pressure")`..........(Eqn. 4) `=(22.5)/(37.9)=0.59` |
|
| 16925. |
Which of the following produces another air pollutant by reacting with oxides of nitrogen in presence of sunlight ? |
| Answer» Answer :C | |
| 16926. |
Which of the following alcohol is least soluble in water ? |
|
Answer» `CH_3OH` |
|
| 16927. |
Which has maximum volume at S.T.P.? |
|
Answer» `1.5xx10^(23)` molecules of `CO_(2)` `= (22.4Lxx1.5xx10^(23))/(6.02xx10^(23))=5.6 L` (B) Volume of 1 g of `H_(2)`(0.5 mol) at S.T.P. `= (22.4L)/(2) = 11.2L` (C) VOUME of 4 g of `O_(2)`(0.125 mol) at S.T.P. = 2.8 L (D) Volume of 16 g of `SO_(3)`(0.2 mol) at S.T.P. = 4.48 L (Molar mass of `H_(2), O_(2)` and `SO_(3)` are 32 g and 80 g `mol^(-1)` respectively) Thus 1 g of `H_(2)` at S.T.P. has largest volume |
|
| 16928. |
What final product(s) is/are formed in the following series of reactons ? Concentrated borax solution + silver nitrate solution to Precipitate underset("boiling")overset(H_(2)O)to Products (final) |
|
Answer» `Ag_(3)BO_(3)` `2AgBO_(2)darr +3H_(2)O underset(Delta//H_(2)O)overset("Hydrolysis")toAg_(2)Odarr("brown")+2H_(3)BO_(3)` |
|
| 16929. |
What percent of voids are occupid by Zn^(2+) ions in ZnS crystal ? |
| Answer» ANSWER :A | |
| 16930. |
What weight of the non-volatile solute urea' (NH_(2)-CO-NH_(2)) needs to be dissolved in 100 g of water in order to decrease the vapour pressure of water by 25%? What will be the molality of the solution? |
| Answer» SOLUTION :111.12 G, 18.52 m | |
| 16931. |
The standard electrode potential of a metal-metal ion (Ag//Ag^(+)) and metal- sparingly soluble salt anion (Ag|AgCl|Cl^(-)) are related as : |
|
Answer» `E_(AG^(+)|Ag)^(@)=E_(Cl^(-) |AgCl|Ag)^(@) + (RT)/(F) ln K_(SP)` |
|
| 16932. |
What do you understand by Hybridisation ? Explain different types of hybridisation involving s and p orbitals. |
|
Answer» SOLUTION :Hybridisation : "intermixing of atomic orbitals of almost equal energies of an atom and their redistribution into an equal number of identical orbitals is called, 'hybridisation'. Examples : Let us see the three types of hybridisations - `sp^(3), sp^(2)` and sp. 1) `sp^(3)` Hybridisation : The phenomenon of intermixing of one 's' ORBITAL and three 'p' orbitals forming four `'sp^(3)'` hybrid orbitals is called `sp^(3)` hybirdisation. Each of the `sp^(3)` hybrid orbitals possess `1/4` of s - character and `3/4` of p character. The bond angle in-betweeen any two `sp^(3)` hybrid orbitals is `109^(@)28'`. The shape of the molecule in which the central atom UNDERGOES `sp^(3)` hybridisaition is tetrahedral.  Example : Formation of Methane `(CH_(4))` molecule : In the formation of methane molecule the central carbon atom undergoes `sp^(3)` hybridisation in its excited state. As a result of which four `sp^(3)` hybrid orbitals will form on it. All the four `sp^(3)` hybrid orbitals possess bond pair of ELECTRONS. Now, the four `sp^(3)` hybrid orbitals overlap head - head with '1s' orbitals of four 'H' atoms forming `CH_(4)` molecule. The shape of the molecule is tetrahedral with a bond angle of `109^(@)28'`. C(Z) = 6 `"" 1s^(2)2s^(2)2P^(2)` Ground state `"" 1s^(2)2s^(2)2p^(1)2p^(1)` Excited state `""underbrace(1s^(2)2s^(1)2p_(x)^(1)2p_(y)^(1)2p_(z)^(1))_(sp^(3)`  2) `sp^(2)` Hybridisation : The phenomenon of intermixing of one 's' orbital and two 'p' orbitals forming three `'sp^(2)'` hybrid orbitals is called `sp^(2)` hybridisation. Each of the `sp^(2)` hybrid orbitals possesses `1/3` s - character and `2/3` p - character. The bond angle in between any two `sp^(2)` hybrid orbitals is `120^(@)`. The shape of the molecule in which the central atom undergoes `sp^(2)` hybridisation is plane triangular.  Example : Formation of Boron trichloride `(BCl_(3))` molecule : In the formation of `BCl_(3)` molecule the central boron atom undergoes `sp^(2)` hybridisation in its excited state `(1s^(2)2s^(1)2p_(x)^(1)2p_(y)^(1)2p_(z)^(0))`. As a result of which three `sp^(2)` hybrid orbitals will form on it. All the three hybrid orbitals possess an electron each. Now, the three `sp^(2)` hybrid orbitals overlap head - head with half - filled `'3p_(z)` orbitals of three chlorine atoms forming `BCl_(3)` molecule. The shape of the molecule is plane triangular with a bond angle of `120^(@)`.  3) sp Hybridisation : The phenomenon of intermixing of one 's' orbital and one 'p' orbital of an atom forming two 'sp' hybrid orbitals is called sp hybridisation. Each of the sp hybrid orbitals possesses `1/2` s - character and `1/2` p - character. The bond angle in-between the two hybrid orbitals is `180^(@)`. The shape of the molecule in which the central atom undergoes sp hybridisation is linear.  Example : Formation of Beryllium chloride `(BeCl_(2))` : In the formation of `BeCl_(2)` molecule the central 'Be' atom undergoes sp hybridisation in its excited state `(1s^(2)2s^(1)2p_(x)^(1)2p_(y)^(0)2p_(z)^(0))`. As a result of which two sp hybrid orbitals will form on it. The two hybrid orbitals contain an electron, each. Now, the two sp hybrid orbitals overlap head - head with half - filled `'3p_(z)'` orbitals of two chlorine atoms forming `BeCl_(2)` molecule. The shape of the molecule is linear with a bond angle is `180^(@)`. 
|
|
| 16933. |
Which of the followingis optically inactive ? [Where a, b =monodentate ligands, AA = symmetrical bidentate ligand] |
|
Answer» Cis-`[M("AA")_2ab]^(n PN)` |
|
| 16935. |
Which of the following statements are correct ? (i) Ionic product of water (K_(w))=[H^(+)][OH^(-)]=10^(-14)M^(2) (ii) At 298K [H^(+)]=[OH^(-)]=10^(-7) (iii) K_(w) does not depend upon temperature (iv) Molarity of pure water = 55.55 M |
|
Answer» I, II and iii |
|
| 16936. |
Write the chemical equation for the reaction between ethylamine and nitrous acid and name the organic compound formed. |
| Answer» SOLUTION :`UNDERSET("ETHYLAMINE")(C_2 H_5 NH_2 ) + HNO_2to underset("ETHANOL ")(C_2 H_5 OH ) +N_2 +H_2 O` | |
| 16937. |
Whichof the following reaction(s) take place in Bessemer converter for the extraction of Cu? |
|
Answer» `2CuFeS_(2) + 4O_(2) rarr Cu_(2)S + 2FeO + 3SO_(2)` |
|
| 16938. |
There are two nodes in the radial probability distribution curve for the orbital with |
|
Answer» n=2,n=0 |
|
| 16939. |
Ziegler Natta catalyst is used in preparation of which of the following ? |
| Answer» SOLUTION :HDP | |
| 16941. |
When NaCl is heated with conc. H_2SO_4 and solid K_2Cr_2O_7, we get: |
|
Answer» CHROMYL chloride |
|
| 16942. |
Which of the following will produce same visual change as p-1 with Br_(2) water? |
|
Answer»
|
|
| 16943. |
when potassium burns in excess supply of air ( oxygen),it forms :- |
|
Answer» oxide |
|
| 16944. |
What is the relationship between P_(1) and P_(2) |
|
Answer» GEOMETRICAL isomers 
|
|
| 16945. |
Triethylamine reacts with HCland NaNO_(2) gives |
|
Answer» triethyl nitroso AMINE |
|
| 16946. |
When any solution passes through a cation exchange resin that is in acidic form, H^(+) ion of the solution. A solution containing 0.319 g of an isomer with molecular formula CrCl_(3).6H_(2)O is passed through a cation exchange resin in acidic form. The diluted solution requires 19cm^(3) of 0.125 N NaOH. The isomer is : |
|
Answer» triaquatrichlorochrominum (III) chloride trihydrate `0.319/266.5 = 0.00119` `CrCl_(3).6H_(2)O to 0.00119` mole, `[Cr(H_(2)O)_(5)Cl]Cl_(2).H_(2)Oto 2CL^(-)to 2H^(+)` `2H^(+)` requires `to 2OH^(-)` `0.00119 xx 2` MOLES of `Cl^(-1)=nH^(+)` `1000 xx 0.00238`=2.38 moles |
|
| 16947. |
What will be the notmality of resulting solution obtained by mixing 4 mL 0.05 M H_(2)SO_(4(aq)) solution and 6 mL 0.3 M _(2)SO_(4(aq)) ? |
|
Answer» 0.175 N `= (0.05xx4+0.3xx6)/(4+6)=(0.2+1.8)/(10)=0.2` Now, `N = M xx2=0.2xx2=0.4` |
|
| 16948. |
Which of the following is not correct regarding bond energies |
|
Answer» The extent of overlap of the atomic orbitals decreases as the size of the atoms INCREASE |
|
| 16949. |
Two possible stereoisomers for |
|
Answer» enantiomers |
|
