The correct sequence of correct reagents for the following transformation is :-

Question: The correct sequence of correct reagents for the following transformation is :- (i) $\mathrm{Fe}, \mathrm{HCl}$ (ii) $\mathrm{Cl}_{2}, \mathrm{HCl}$, (iii) $\mathrm{NaNO}_{2}, \mathrm{HCl}, 0^{\circ} \mathrm{C}$ (iv) $\mathrm{H}_{2} \mathrm{O} / \mathrm{H}^{+}$(i) $\mathrm{Fe}, \mathrm{HCl}$ (ii) $\mathrm{NaNO}_{2}, \mathrm{HCl}, 0^{\circ} \mathrm{C}$ (iii) $\mathrm{H}_{2} \mathrm{O} / \mathrm{H}^{+}$ (iv) $\mathrm{Cl}_{2}, \mathrm{FeCl}_{3}$(i) $\mathrm{Cl}_{2}, \mathrm{FeCl}_{3}$ (ii...

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The compound/s which will show significant intermolecular H–bonding is/are :

Question: The compound/s which will show significant intermolecular Hbonding is/are : (b) only(c) only(a) and (b) only(a), (b) and (c)Correct Option: 1 Solution: (a) Shows intra molecular H-bonding (b) Shows significant intermolecular H-bonding (c) It do not show intermolecular H-bonding due to steric hindrance....

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Solve this following

Question: The $\mathrm{Eu}^{2+}$ ion is a strong reducing agent in spite of its ground state electronic configuration (outermost): [Atomic number of Eu =63]$4 f^{7} 6 \mathrm{~s}^{2}$$4 f^{6}$$4 f^{7}$$4 f^{6} 6 \mathrm{~s}^{2}$Correct Option: 3, Solution: $\mathrm{Eu} \rightarrow[\mathrm{Xe}] 4 \mathrm{f}^{7} 6 \mathrm{~s}^{2}$ $\mathrm{Eu}^{2+} \rightarrow[\mathrm{Xe}] 4 \mathrm{f}^{7}$...

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Match List I with List II :

Question: Match List I with List II : Choose the correct answer from the options given below:(a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)(a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)(a)-(iv), (b)-(ii), (c)-(iii), (d)-(i)$(\mathrm{a})-(\mathrm{i}),(\mathrm{b})-(\mathrm{ii}),(\mathrm{c})-(\mathrm{iii}),(\mathrm{d})-(\mathrm{iv})$Correct Option: 1 Solution: (a) $\mathrm{C}_{\mathrm{S}} \mathrm{I}$ salt is poor water soluble due to it's low hydration energy (b) $\mathrm{NaHCO}_{3}$ is used in fire extinguisher (...

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The number of lone pairs of electrons on the central

Question: The number of lone pairs of electrons on the central I atom in $\mathrm{I}_{3}^{-}$is Solution: The number of lone pairs of electron on the central atom is 3....

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A biodegradable polyamide can be made from:

Question: A biodegradable polyamide can be made from:Glycine and isopreneHexamethylene diamine and adipic acidGlycine and aminocaproic acidStyrene and caproic acidCorrect Option: , 3 Solution: A biodegradable polyamide nylon-2-Nylon-6 in made from glycine and amino caproic acid...

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What is A in the following reaction?

Question: What is A in the following reaction? Correct Option: , 4 Solution:...

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Solve this

Question: For above chemical reactions, identify the correct statement from the following:Both compound 'A' and compound 'B' are dicarboxylic acidsBoth compound 'A' and compound 'B' are diolsCompound 'A' is diol and compound 'B' is dicarboxylic acidCompound 'A' is dicarboxylic acid and compound 'B' is diolCorrect Option: , 4 Solution:...

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In the following the correct bond order sequence is:

Question: In the following the correct bond order sequence is:$\mathrm{O}_{2}^{2-}\mathrm{O}_{2}^{+}\mathrm{O}_{2}^{-}\mathrm{O}_{2}$$\mathrm{O}_{2}^{+}\mathrm{O}_{2}^{-}\mathrm{O}_{2}^{2-}\mathrm{O}_{2}$$\mathrm{O}_{2}^{+}\mathrm{O}_{2}\mathrm{O}_{2}^{-}\mathrm{O}_{2}^{2-}$$\mathrm{O}_{2}\mathrm{O}_{2}^{-}\mathrm{O}_{2}^{2-}\mathrm{O}_{2}^{+}$Correct Option: , 3 Solution: $\mathrm{O}_{2}$ (16 electrons) $\sigma_{1 \mathrm{~s}}^{2}, \sigma_{1 \mathrm{~s}}^{* 2}, \sigma_{2 \mathrm{~s}}^{2}, \sigm...

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Arrange the following conformational isomers of n-butane in order of their increasing potential energy:

Question: Arrange the following conformational isomers of n-butane in order of their increasing potential energy: $\mathrm{II}\mathrm{III}\mathrm{IV}\mathrm{I}$$\mathrm{I}\mathrm{IV}\mathrm{III}\mathrm{II}$$\mathrm{II}\mathrm{IV}\mathrm{III}\mathrm{I}$$\mathrm{I}\mathrm{III}\mathrm{IV}\mathrm{II}$Correct Option: , 4 Solution: More stable less potential energy. Stability order : I III IV II So Potential energy: II $$ IV $$ III $$ I...

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Select the correct statements.

Question: Select the correct statements. (A) Crystalline solids have long range order. (B) Crystalline solids are isotropic. (C) Amorphous solid are sometimes called pseudo solids. (D) Amorphous solids soften over a range of temperatures. (E) Amorphous solids have a definite heat of fusion. Choose the most appropriate answer from the options given below.(A), (B), (E) only(B), (D) only(C), (D) only(A), (C), (D) onlyCorrect Option: , 4 Solution: (A) Crystalline solids have definite arrangement of ...

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Solve this

Question: Which among the above compound/s does/do not form Silver mirror when treated with Tollen's reagent?(I), (III) and (IV) onlyOnly (IV)Only (II)(III) and (IV) onlyCorrect Option: , 3 Solution: Aldehydes give $\oplus$ ve Tollen's Test (Silver mirror...

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Identify the incorrect statement

Question: Identify the incorrect statement from the followingAmylose is a branched chain polymer of glucoseStarch is a polymer of $\alpha-D$ glucose$\beta$-Glycosidic linkage makes cellulose polymerGlycogen is called as animal starchCorrect Option: 1 Solution: Amylose is a linear chain polymer of $\alpha$-D-glucose while amylopectine is branched chain polymer of $\alpha$-D-glucose....

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Solve this following

Question: $\mathrm{A}_{3} \mathrm{~B}_{2}$ is a sparingly soluble salt of molar mass $\mathrm{M}\left(\mathrm{g} \mathrm{mol}^{-1}\right)$ and solubility $\mathrm{x} \mathrm{g} \mathrm{L}^{-1}$. The solubility product satisfies $\mathrm{K}_{\mathrm{sp}}=a\left(\frac{\mathrm{x}}{\mathrm{M}}\right)^{5} .$ The value of $a$ is (Integer answer) Solution: $\mathrm{A}_{3} \mathrm{~B}_{2}(\mathrm{~s}) \rightleftharpoons 3 \mathrm{~A}_{(24)}^{+2}+2 \mathrm{~B}_{(4 q)}^{-3}$ $3 \mathrm{~s} \quad 2 \mathrm...

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Number of Cl = O bonds in chlorous acid,

Question: Number of $\mathrm{Cl}=\mathrm{O}$ bonds in chlorous acid, chloric acid and perchloric acid respectively are :3,1 and 14,1 and 01,1 and 31,2 and 3Correct Option: , 3 Solution:...

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Consider the complete combustion of butane,

Question: Consider the complete combustion of butane, the amount of butane utilized to produce $72.0 \mathrm{~g}$ of water is ________$\times 10^{-1} \mathrm{~g}$. (in nearest integer) Solution: $\mathrm{C}_{4} \mathrm{H}_{10}+\frac{13}{2} \mathrm{O}_{2} \longrightarrow 4 \mathrm{CO}_{2}+5 \mathrm{H}_{2} \mathrm{O}$ Moles of $\mathrm{H}_{2} \mathrm{O}=\frac{72}{18}=4$ Moles of $\mathrm{C}_{4} \mathrm{H}_{10}$ used $=\frac{1}{5} \times 4$ Weight of $\mathrm{C}_{4} \mathrm{H}_{10}$ used $=\frac{4}...

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In stratosphere most of the ozone formation is assisted by :

Question: In stratosphere most of the ozone formation is assisted by :cosmic rays.$\gamma$-rays.ultraviolet radiation.visible radiations.Correct Option: , 3 Solution: Ozone in the stratosphere is a product of UV radiations acting on dioxygen $\left(\mathrm{O}_{2}\right)$ molecules. $\mathrm{O}_{2}(\mathrm{~g}) \stackrel{\mathrm{UV}}{\longrightarrow} \mathrm{O}(\mathrm{g})+\mathrm{O}(\mathrm{g})$ $\mathrm{O}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g}) \stackrel{\mathrm{UV}}{\rightleftharpoons} \mathr...

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If the Thompson model of the atom was correct,

Question: If the Thompson model of the atom was correct, then the result of Rutherford's gold foil experiment would have been :All of the $\alpha$-particles pass through the gold foil without decrease in speed.$\alpha$-Particles are deflected over a wide range of angles.All $\alpha$-particles get bounced back by $180^{\circ}$$\alpha$-Particles pass through the gold foil deflected by small angles and with reduced speed.Correct Option: , 4 Solution: As in Thomson model, protons are diffused (charg...

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When 10 mL of an aqueous solution

Question: When $10 \mathrm{~mL}$ of an aqueous solution of $\mathrm{Fe}^{2+}$ ions was titrated in the presence of dil $\mathrm{H}_{2} \mathrm{SO}_{4}$ using diphenylamine indicator, $15 \mathrm{~mL}$ of $0.02 \mathrm{M}$ solution of $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ was required to get the end point. The molarity of the solution containing $\mathrm{Fe}^{2+}$ ions is $\mathrm{x} \times 10^{-2} \mathrm{M}$. The value of $\mathrm{x}$ is_________ (Nearest integer) Solution: milli-equi...

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Solve this following

Question: $\operatorname{Ge}(Z=32)$ in its ground state electronic configuration has x completely filled orbitals with $\mathrm{m}_{l}=0 .$ The value of $\mathrm{x}$ is Solution: Completely filled orbital with $\mathrm{m}_{t}=0$ are $=1+1+1+1+1+1+1$ $=7$ So Answer is 7...

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The conditions given below are in the context of observing

Question: The conditions given below are in the context of observing Tyndall effect in colloidal solutions: (A) The diameter of the colloidal particles is comparable to the wavelength of light used. (B) The diameter of the colloidal particles is much smaller than the wavelength of light used. (C) The diameter of the colloidal particles is much larger than the wavelength of light used. (D) The refractive indices of the dispersed phase and the dispersion medium are comparable. (E) The dispersed ph...

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A home owner uses

Question: A home owner uses $4.00 \times 10^{3} \mathrm{~m}^{3}$ of methane $\left(\mathrm{CH}_{4}\right)$ gas, (assume $\mathrm{CH}_{4}$ is an ideal gas) in a year to heat his home. Under the pressure of $1.0 \mathrm{~atm}$ and $300 \mathrm{~K}$, mass of gas used is $\times \times 10^{5} \mathrm{~g}$. The value of $x$ is _________ (Nearest integer) (Given $\mathrm{R}=0.083 \mathrm{~L}$ atm $\mathrm{K}^{-1} \mathrm{~mol}^{-1}$ ) Solution: $\mathrm{n}\left(\mathrm{CH}_{4}\right)=\frac{\mathrm{PV}...

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Match List - I with List - II :

Question: Match List - I with List - II : Choose the correct answer from the options given below:(a) - (iii), (b) - (iv), (c) - (i), (d) - (ii)(a) - (iv), (b) - (i), (c) - (iii), (d) - (ii)(a) - (i), (b) - (ii), (c) - (iii), (d) - (iv)(a) - (iii), (b) - (iv), (c) - (ii), (d) - (i)Correct Option: 1 Solution: Official Ans. by NTA (1)...

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Given below are two statements :

Question: Given below are two statements : Statement I : Ethyl pent-4-yn-oate on reaction with $\mathrm{CH}_{3} \mathrm{MgBr}$ gives a $3^{\circ}$-alcohol. Statement II : In this reaction one mole of ethyl pent-4-yn-oate utilizes two moles of $\mathrm{CH}_{3} \mathrm{MgBr}$. In the light of the above statements, choose the most appropriate answer from the options given below :Both Statement I and Statement II are false.Statement I is false but Statement II is true.Statement I is true but Stateme...

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According to the following figure, the magnitude of the enthalpy change of the reaction

Question: According to the following figure, the magnitude of the enthalpy change of the reaction $\mathrm{A}+\mathrm{B} \rightarrow \mathrm{M}+\mathrm{N}$ in $\mathrm{kJ} \mathrm{mol}^{-1}$ is equal to____________(Integer answer) Solution: $\Delta \mathrm{H}=\mathrm{E}_{\mathrm{a}_{\mathrm{f}}}-\mathrm{E}_{\mathrm{a}_{\mathrm{b}}}$ $=20-65$ $=-45 \mathrm{KJ} / \mathrm{mol}$ $|\Delta \mathrm{H}|=45 \mathrm{KJ} / \mathrm{mol}$...

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