Amongst the following statements regarding adsorption,

Question: Amongst the following statements regarding adsorption, those that are valid are : (a) $\Delta \mathrm{H}$ becomes less negative as adsorption proceeds. (b) On a given adsorbent, ammonia is adsorbed more than nitrogen gas. (c) On adsorption, the residual force acting along the surface of the adsorbent increases. (d) With increase in temperature, the equilibrium concentration of adsorbate increases.(b) and (c)(a) and (b)(d) and (a)(c) and $(d)$Correct Option: , 2 Solution: (a) Since adso...

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The total number of monohalogenated organic products in the following (including stereoisomers) reaction is

Question: The total number of monohalogenated organic products in the following (including stereoisomers) reaction is $\mathrm{A}$ (simplest optically active alkene) $\frac{\text { (i) } \mathrm{H}_{2} / \mathrm{Ni} / \Delta}{\text { (ii) } \mathrm{X}_{2} / \Delta}$ Solution: Alter Str. of Tri peptide...

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An element with molar mass

Question: An element with molar mass $2.7 \times 10^{-2} \mathrm{kgmol}^{-1}$ forms a cubic unit cell with edge length $405 \mathrm{pm}$. If its density is $2.7 \times 10^{3} \mathrm{kgm}^{-3}$, the radius of the element is approximately $\times 10^{-12} \mathrm{~m}$ (to the nearest integer). Solution: $\mathrm{d}=\frac{\mathrm{Z}\left(\frac{\mathrm{M}}{\mathrm{N}_{\mathrm{A}}}\right)}{\mathrm{a}^{3}}$ $2.7 \times 10^{3}=\mathrm{z} \frac{\left(\frac{2.7 \times 10^{-2}}{6 \times 10^{23}}\right)}{...

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The one that is not expected to show isomerism is:

Question: The one that is not expected to show isomerism is:$\left[\mathrm{Ni}\left(\mathrm{NH}_{3}\right)_{4}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}\right]^{2+}$$\left[\mathrm{Ni}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}\right]$$\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}\right]$$\left[\mathrm{Ni}(\mathrm{en})_{3}\right]^{2+}$Correct Option: , 2 Solution: $\left[\mathrm{Ni}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}\right]$ is tetrahedral complex, therefore ...

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The photoelectric current from $mathrm{Na}$

Question: The photoelectric current from Na (work function, $\mathrm{w}_{0}=2.3 \mathrm{eV}$ ) is stopped by the output voltage of the cell $\mathrm{Pt}(\mathrm{s})\left|\mathrm{H}_{2}(\mathrm{~g}, 1 \mathrm{bar})\right| \mathrm{HCl}(\mathrm{aq} ., \mathrm{pH}=1)|\mathrm{AgCl}(\mathrm{s})| \mathrm{Ag}(\mathrm{s})$ The $\mathrm{pH}$ of aq. $\mathrm{HCl}$ required to stop the photoelectric current from $\mathrm{K}\left(\mathrm{w}_{0}=2.25 \mathrm{eV}\right)$, all other conditions remaining the sam...

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Two elements A and B have similar chemical properties.

Question: Two elements $A$ and $B$ have similar chemical properties. They don't form solid hydrogencarbonates, but react with nitrogen to form nitrides. A and B, respectively, are :$\mathrm{Na}$ and $\mathrm{C}$Li and Mg$\mathrm{Cs}$ and $\mathrm{Ba}$$\mathrm{Na}$ and $\mathrm{Rb}$Correct Option: , 2 Solution: Both $\mathrm{Li}$ and $\mathrm{Mg}$ form nitride when reacts directly with nitrogen. The hydrogen carbonate of both $\mathrm{Li}$ and $\mathrm{Mg}$ does not exist in solid state. All alka...

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The mole fraction of glucose

Question: The mole fraction of glucose $\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)$ in an aqueous binary solution is $0.1$. The mass percentage of water in it, to the nearest integer, is Solution: $\mathrm{X}_{\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}}=0.1$ Let total mole is 1 mol then mole of glucose will be $0.1$ and mole of water will be $0.9$ so mass $\%$ of water $=\frac{0.9 \times 18}{0.1 \times 180+0.9 \times 18} \times 100$ $=47.36$ Ans : 47...

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The size of a raw mango shrinks to a much smaller size when kept

Question: The size of a raw mango shrinks to a much smaller size when kept in a concentrated salt solution. Which one of the following processes can explain this ?DiffusionDialysisOsmosisReverse osmosisCorrect Option: , 3 Solution: Raw mango shrink in salt solution due to net transfer of water molecules from mango to salt solution due to phenomenon of osmosis....

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An organic compound 'A' ( C9H10O ) when treated with conc.

Question: An organic compound ' $\mathrm{A}^{\prime}\left(\mathrm{C}_{9} \mathrm{H}_{10} \mathrm{O}\right)$ when treated with conc. HI undergoes cleavage to yield compounds ' $B$ ' and ' $C$ '. 'B' gives yellow precipitate with $\mathrm{AgNO}_{3}$ where as ' $\mathrm{C}$ ' tautomerizes to 'D', 'D' gives positive idoform test. 'A' could be :Correct Option: , 2 Solution:...

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The volume strength

Question: The volume strength of $8.9 \mathrm{M} \mathrm{H}_{2} \mathrm{O}_{2}$ solution calculated at $273 \mathrm{~K}$ and $1 \mathrm{~atm}$ is $\left(\mathrm{R}=0.0821 \mathrm{~L} \mathrm{~atm} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right)$ (rounded off to the nearest integer) Solution: Volume strength of $\mathrm{H}_{2} \mathrm{O}_{2}$ at $1 \mathrm{~atm}$ 273 kelvin $=\mathrm{M} \times 11.2=8.9 \times 11.2=99.68$ Ans : 100...

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The results given in the below table were obtained during kinetic studies of the following reaction:

Question: The results given in the below table were obtained during kinetic studies of the following reaction: $2 \mathrm{~A}+\mathrm{B} \longrightarrow \mathrm{C}+\mathrm{D}$ $X$ and $Y$ in the given table are respectively :$0.3,0.4$$0.4,0.3$$0.4,0.4$$0.3,0.3$Correct Option: 1 Solution: From rate law $=K[A]^{x}[B]^{y}$ $6 \times 10^{-3}=K(0.1)^{x}(0.1)^{y}$.........(1) $2.4 \times 10^{-2}=\mathrm{K}(0.1)^{\mathrm{x}}(0.2)^{\mathrm{y}}$.........(2) $1.2 \times 10^{-2}=\mathrm{K}(0.2)^{\mathrm{x}...

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The antifertility drug 'Novestrol" can react with :

Question: The antifertility drug 'Novestrol" can react with : $\mathrm{Br}_{2} /$ water $; \mathrm{ZnCl}_{2} / \mathrm{HCl} ; \mathrm{FeCl}_{3}$Alcoholic $\mathrm{HCN} ; \mathrm{NaOCl} ; \mathrm{ZnCl}_{2} / \mathrm{HCl}$$\mathrm{Br}_{2} /$ water; $\mathrm{ZnCl}_{2} / \mathrm{HCl} ; \mathrm{NaOCl}$$\mathrm{ZnCl}_{2} / \mathrm{HCl} ; \mathrm{FeCl}_{3} ;$ Alcoholic $\mathrm{HCN}$Correct Option: 1 Solution: Ethynylestradiol (novestrol) gives (1) $\mathrm{Br}_{2}+\mathrm{H}_{2} \mathrm{O}$ test (2) L...

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Which of the following is false ?

Question: Let $\mathrm{C}_{\mathrm{NaCl}}$ and $\mathrm{C}_{\mathrm{BaSO}_{4}}$ be the conductances (in $\mathrm{S}$ ) measured for saturated aqueous solutions of $\mathrm{NaCl}$ and $\mathrm{BaSO}_{4}$, respectively, at a temperature T. Which of the following is false ?Ionic mobilities of ions from both salts increase with $\mathrm{T}$$\mathrm{C}_{\mathrm{NaCl}} \gg \mathrm{C}_{\mathrm{BaSO}_{4}}$ at a given $\mathrm{T}$$\mathrm{C}_{\mathrm{NaCl}}\left(\mathrm{T}_{2}\right)\mathrm{C}_{\mathrm{N...

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Consider the reaction sequence given below :

Question: Consider the reaction sequence given below : Which of the following statements is true :Changing the concentration of base will have no effect on reaction (1)Changing the concentration of base will have no effect on reaction (2)Changing the base from $\mathrm{OH}^{\ominus}$ to $^{\ominus} \mathrm{OR}$ will have no effect on reaction (2)Doubling the concentration of base will double the rate of both the reactions.Correct Option: 1 Solution: Reaction 1: SN, Reaction $2: \mathrm{E}_{2}$ $...

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An acidic buffer is obtained on mixing:

Question: An acidic buffer is obtained on mixing:$100 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{CH}_{3} \mathrm{COOH}$ and $200 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{NaOH}$$100 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{CH}_{3} \mathrm{COOH}$ and $100 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{NaOH}$$100 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{HCl}$ and $200 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{CH}_{3} \mathrm{COONa}$$100 \mathrm{~mL}$ of $0.1 \mathrm{M} \mathrm{HCl}$ and $200 \mathrm{~mL}$ o...

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The atomic number of the element unnilennium is :

Question: The atomic number of the element unnilennium is : 119108102109Correct Option: 4, Solution: $\begin{array}{lll}1 0 9\end{array}$ un nil enn Hence correct name $\rightarrow$ unnilennium...

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Simplified absorption spectra of three complexes ((i),

Question: Simplified absorption spectra of three complexes ((i), (ii) and (iii)) of $\mathrm{M}^{\mathrm{nt}}$ ion are provided below; their $\lambda_{\max }$ values are marked as $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ respectively. The correct match between the complexes and their $\lambda_{\max }$ values is : (i) $\left[\mathrm{M}(\mathrm{NCS})_{6}\right]^{(-6+\mathrm{n})}$ (ii) $\left[\mathrm{MF}_{6}\right]^{(-6+\mathrm{n})}$ (iii) $\left[\mathrm{M}\left(\mathrm{NH}_{3}\right)_{6}\right]^{...

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The number of subshells associated with

Question: The number of subshells associated with $\mathrm{n}=4$ and $m=-2$ quantum numbers is:48162Correct Option: , 4 Solution: For $n=4$ $\ell=0,1,2,3$ $\therefore 4 \mathrm{~d} \ 4 \mathrm{f}$ subshell associated with $\mathrm{n}=4, \mathrm{~m}=-2$...

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Of the species,

Question: Of the species, $\mathrm{NO}, \mathrm{NO}^{+}, \mathrm{NO}^{2+}, \mathrm{NO}^{-}$, the one with minimum bond strength is : $\mathrm{NO}^{2+}$$\mathrm{NO}^{+}$$\mathrm{NO}$$\mathrm{NO}^{-}$Correct Option: , 4 Solution: Bond order of $\mathrm{NO}^{2+}=2.5$ Bond order of $\mathrm{NO}^{+}=3$ Bond order of $\mathrm{NO}=2.5$ Bond order of $\mathrm{NO}^{-}=2$ Bond order $\alpha$ bond strength....

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Three elements X, Y and Z are in the 3^rd period of the periodic table.

Question: Three elements $X, Y$ and $Z$ are in the $3^{\text {rd }}$ period of the periodic table. The oxides of X, Y and Z, respectively, are basic, amphoteric and acidic. The correct order of the atomic numbers of $X, Y$ and $Z$ is:$ZYX$$\mathrm{X}\mathrm{Z}\mathrm{Y}$$\mathrm{X}\mathrm{Y}\mathrm{Z}$$\mathrm{Y}\mathrm{X}\mathrm{Z}$Correct Option: , 3 Solution: When we are moving from left to right in a periodic table acidic character of oxides increases (as well as atomic number of atom increa...

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The major product obtained from

Question: The major product obtained from $\mathrm{E}_{2}$-elimination of 3-bromo-2-fluoropentane is:Correct Option: , 4 Solution:...

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Glycerol is separated in soap industries by :

Question: Glycerol is separated in soap industries by : Steam distillationDifferential extraction Distillation under reduced pressureFractional distillationCorrect Option: , 3 Solution: Glycerol is separated by reduced pressure distillation in soap industries....

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The shape/structure of [XeF5] and XeO3F2, respectivel. are:

Question: The shape/structure of $\left[\mathrm{XeF}_{5}\right]^{-}$and $\mathrm{XeO}_{3} \mathrm{~F}_{2}$, respectively, are :pentagonal planar and trigonal bipyramidaltrigonal bipyramidal and pentagonal planaroctahedral and square pyramidaltrigonal bipyramidal and trigonal bipyramidalCorrect Option: 1 Solution:...

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Which one of the following compounds possesses the most acidic hydrogen ?

Question: Which one of the following compounds possesses the most acidic hydrogen ? Correct Option: , 4 Solution: Due to presence of $3(-R)$ groups...

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Two compounds A and B with same molecular formula

Question: Two compounds A and B with same molecular formula $\left(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}\right)$ undergo Grignard's reaction with methylmagnesium bromide to give products $\mathrm{C}$ and $\mathrm{D}$. products $\mathrm{C}$ and $\mathrm{D}$ show following chemical tests. Correct Option: , 3 Solution:...

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