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An organic compound having molecular mass 60 is found to contain $C=20 \%, H=6.67 \%$ and $N = 46.67 \%$ while rest is oxygen. On heating it gives $NH_3$ along with a solid residue. The solid residue give violet colour with alkaline copper sulphate solution. The compound is :

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The amount of solid $NH_4HS$ is placed in a flask already containing ammonia gas at a certain temperature and 0.50 atm pressure. Ammonium hydrogen sulphide decomposes to yield $NH_3$ and $H_2S$ gases in the flask. When the decomposition reaction reaches equilibrium, the total pressure in the flask rises to 0.84 atm ? The equilibrium constant for $NH_2HS$ decomposition at this temperature is :

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If the bond dissociation energies of $XY, X_2$ and $Y_2$ (all diatomic molecules) are in the ratio of $1 : 1 : 0.5$ and $\Delta H_f$ for the formation of $XY$ is $-200 \; kJ \; mol^{-1}$. The bond dissociation energy of $X_2$ will be :

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p-cresol reacts with chloroform in alkaline medium to give the compound A which adds hydrogen cyanide to form, the compound B. The latter on acidic hydrolysis gives chiral carboxylic acid. The structure of the carboxylic acid is :

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Reaction of cyclohexanone with dimethlamine in the presence of catalic amount of an acid forms a compound. Water during the reaction is continuously removed. The compound formed is generally known as :

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The value of the 'spin only' magnetic moment for one of the following configurations is 2.84 BM. The correct one is :

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Which of the following factors may be regarded as the main cause of lanthanide contraction ?

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Which of the following statements in relation to the hydrogen atom is correct ?

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The structure of diborane $(B_2H_6)$ contains :

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The reaction is fastest when $X$ is :

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Equimolar solutions in the same solvent have :

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Elimination of bromine from 2-bromobutane results in the formation of :

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Which of the following is fully fluorinated polymer ?

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Acid catalyzed hydration of alkenes except ethene leads to the formation of :

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Amongst the following the most basic compound is :

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Which types of isomerism is shown by 2, 3-dichlorobutane ?

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Which one of the following methods is neither meant for the synthesis nor for separation of amines ?

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Alkyl halides react with dialkyl copper reagents to give :

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Of the five isomeric hexanes, the isomer which can give two monochlorinated compound is :

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Among the following acids which has the lowest $pK_a$ value ?

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In both DNA and RNA, heterocylic base and phosphate ester linkages are at :

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Tertiary alkyl halides are practically inert to substitution by $S_N 2$ mechanism because of :

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The decreasing order of nucleophilicity among the nucleophiles :

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Reaction of one molecule of HBr with one molecule of 1, 3-butadiene at $40^{\circ} C$ gives predominantly :

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A photon of hard gamma radiation knocks a proton out of $^{24}_{12} Mg$ nucleus to form :

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The best reagent to convert pent-3-en-2-ol into pent-3-en-2-one is :

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Which one of the following cyano complexes would exhibit the lowest value of paramagnetic behaviour ? (Atomic no. Cr = 24, Mn = 25, Fe = 26, Co = 27 )

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Which of the following compounds shows optical isomerism ?

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2-methylbutane on reacting with bromine in the presence of sunlight gives mainly :

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Of the following sets which one does not contain isoelectronic species ?

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In which of the following arrangements the order is not according to the property indicated against it ?

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The IUPAC name of the co-ordination compound $K_3[Fe(CN)_6]$ is :

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The lanthanide contraction is responsible for the fact that :

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In silicon dioxide :

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The oxidation state of chromium in the final product formed by the reaction between $KI$ and acidified potassium dichromate solution is :

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The number and type of bonds between two carbon atoms in calcium carbide are :

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Calomel $(Hg_2Cl_2)$ on reaction with ammonium hydroxide gives :

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The correct order of the thermal stability of hydrogen halides (H-X) is :

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Heating an aqueous solution of aluminium chloride to dryness will give :

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What is the conjugate base of $OH^-$ ?

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The number of hydrogen atom(s) attached to phosphorus atom in hypophosphorous acid is :

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The disperse phase in colloidal iron (III) hydroxide and colloidal gold is positively and negatively charged, respectively. Which of the following statements is not correct ?

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The molecular shapes of $SF_4, CF_4 $ and $XeF_4$ are :

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Heating mixture of $Cu_2O$ and $Cu_2S$ will give

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A schematic plot of $ln \;K_{eq}$ versus inverse of temperature for a reaction is shown below : The reaction must be :

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Based on lattice energy and other considerations which one of the following alkali metal chlorides is expected to have the highest melting point ?

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In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields ? (A) $n = 1, l =0, m =0$ (B) $n = 2, l = 0, m = 0$ (C) $n = 2, l = 1, m = 1 $ (D) $n = 3, l = 2, m = 1$ (E) $n = 3, l = 2, m = 0 $

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If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will :

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Calculate $\land^{\infty} HOAc$ using appropriate molar conductances of the electrolytes listed above at infinite dilution in $H_2O$ at $25^{\circ} C$ :

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During the process of electrolytic refining of copper, some metals present as impurity settle as 'anode mud'. These are :

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