The number of moles of CuO, that will be utilized in Dumas method for estimation nitrogen in a sample of 57.5g of N,

Question: The number of moles of $\mathrm{CuO}$, that will be utilized in Dumas method for estimation nitrogen in a sample of $57.5 \mathrm{~g}$ of $\mathrm{N}, \mathrm{N}$-dimethylaminopentane is____________ $\times 10^{-2}$. (Nearest integer) Solution: Moles of $\mathrm{N}$ in $\mathrm{N}, \mathrm{N}$ - dimethylaminopentane $=\left(\frac{57.5}{115}\right)=0.5 \mathrm{~mol}$ $\Rightarrow \mathrm{C}_{7} \mathrm{H}_{17} \mathrm{~N}+\frac{45}{2} \mathrm{CuO} \rightarrow 7 \mathrm{CO}_{2}+\frac{17}...

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Given below are two statements: One is labelled as Assertion

Question: Given below are two statements: One is labelled as Assertion $\mathbf{A}$ and other is labelled as Reason $\mathbf{R}$. Assertion A : The dihedral angles in $\mathrm{H}_{2} \mathrm{O}_{2}$ in gaseous phase is $90.2^{\circ}$ and in solid phase is $111.5^{\circ}$. Reason $\mathbf{R}$ : The change in dihedral angle in solid and gaseous phase is due to the difference in the intermolecular forces. Choose the most appropriate answer from the options given below for $\mathbf{A}$ and $\mathbf{...

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For the following graphs,

Question: For the following graphs, Choose from the options given below, the correct one regarding order of reaction is :(b) zero order (c) and (e) First order(a) and (b) Zero order (e) First order(b) and (d) Zero order (e) First order(a) and (b) Zero order (c) and (e) First orderCorrect Option: 1 Solution: For zero order reaction's rate $=\mathrm{K}$ [Reactant] $^{0}$ $\Rightarrow \mathrm{r}=\mathrm{k}$ Reactant concentration after time $t \rightarrow$ $\mathrm{C}_{\mathrm{t}}=\mathrm{C}_{0} \m...

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Solve the following

Question: Consider the above reaction, the major product "P" formed is :-Correct Option: , 2 Solution:...

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1 mol of an octahedral metal complex with formula

Question: 1 mol of an octahedral metal complex with formula $\mathrm{MCl}_{3} \cdot 2 \mathrm{~L}$ on reaction with excess of $\mathrm{AgNO}_{3}$ gives 1 mol of $\mathrm{AgCl}$. The denticity of Ligand $\mathrm{L}$ is___________ (Integer answer) Solution: $\mathrm{MCl}_{3} .2 \mathrm{~L}$ octahedral $\mathrm{MCl}_{3} .2 \mathrm{~L} \stackrel{\mathrm{Ex} . \mathrm{AgNO}_{3}}{\longrightarrow} 1$ mole of $\mathrm{AgCl}$ Its means that one Cl ion present in ionization sphere. $\therefore$ formula $=...

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Orlon fibres are

Question: Orlon fibres are made up of:PolyacrylonitrilePolyestersPolyamideCelluloseCorrect Option: 1, Solution: $\rightarrow$ orlon fibers are made up of Polyacrylonitrile...

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Given below are two statements,

Question: Given below are two statements, one is labelled as Assertion (A) and other is labelled as Reason (R). Assertion (R) : Gabriel phthalimide synthesis cannot be used to prepare aromatic primary amines. Reason : Aryl halides do not undergo nucleophilic substitution reaction. In the light of the above statements, choose the correct answer from the options given below :Both (A) and (R) true but (R) is not the correct explanation of (A).(A) is false but $(R)$ is true.Both (A) and (R) true and...

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Which one of the following

Question: Which one of the following $0.10 \mathrm{M}$ aqueous solutions will exhibit the largest freezing point depression?hydrazineglucoseglycine$\mathrm{KHSO}_{4}$Correct Option: , 4 Solution: $\because$ Van't Hoff factor is highest for $\mathrm{KHSO}_{4}$ $\therefore$ colligative property $\left(\Delta \mathrm{T}_{f}\right)$ will be highest for $\mathrm{KHSO}_{4}$...

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Which one of the following set of elements can

Question: Which one of the following set of elements can be detected using sodium fusion extract?Sulfur, Nitrogen, Phosphorous, HalogensPhosphorous, Oxygen, Nitrogen, HalogensNitrogen, Phosphorous, Carbon, SulfurHalogens, Nitrogen, Oxygen, SulfurCorrect Option: 1 Solution: By sodium fusion extract we can detect sulphur, nitrogen, Phosphorous and halogens, because they are converted in to their ionic form with sodium metal....

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Given below are two statements. One is labelled as Assertion

Question: Given below are two statements. One is labelled as Assertion $\mathbf{A}$ and the other is labelled as Reason $\mathbf{R}$. Assertion A : Sharp glass edge becomes smooth on heating it upto its melting point. Reason $\mathbf{R}$ : The viscosity of glass decreases on melting. Choose the most appropriate answer from the options given below.$\mathbf{A}$ is true but $\mathbf{R}$ is falseBoth $\mathbf{A}$ and $\mathbf{R}$ are true but $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A...

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1 kg of 0.75 molal aqueous solution of sucrose can be cooled up to –4°C before freezing.

Question: 1 kg of 0.75 molal aqueous solution of sucrose can be cooled up to 4C before freezing. The amount of ice (in g) that will be separated out is ________ . (Nearest integer) $\left[\right.$ Given : $\left.\mathrm{K}_{\mathrm{r}}\left(\mathrm{H}_{2} \mathrm{O}\right)=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$ Solution: Let mass of water initially present = x gm $\Rightarrow$ Mass of sucrose $=(1000-\mathrm{x}) \mathrm{gm}$ $\Rightarrow$ moles of sucrose $=\left(\frac{1000-x}{...

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Solve this

Question: The given reaction can occur in the presence of : (a) Bromine water (b) $\mathrm{Br}_{2}$ in $\mathrm{CS}_{2}, 273 \mathrm{~K}$ (c) $\mathrm{Br}_{2} / \mathrm{FeBr}_{3}$ (d) $\mathrm{Br}_{2}$ in $\mathrm{CHCl}_{3}, 273 \mathrm{~K}$ Choose the correct answer from the options given below:(b) and (d) only(a) and (c) only(b), (c) and (d) only(a), (b) and (d) onlyCorrect Option: , 3 Solution: Bromine water gives tribromo products, other gives monobromo products in which para is major produc...

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Solve this

Question: Consider the given reaction, the product ' $\mathrm{X}$ ' is:Correct Option: , 4 Solution:...

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Given below are two statements. One is labelled as Assertion

Question: Given below are two statements. One is labelled as Assertion $\mathbf{A}$ and the other is labelled as Reason $\mathbf{R}$. Assertion A : Sharp glass edge becomes smooth on heating it upto its melting point. Reason $\mathbf{R}$ : The viscosity of glass decreases on melting. Choose the most appropriate answer from the options given below.$\mathbf{A}$ is true but $\mathbf{R}$ is falseBoth $\mathbf{A}$ and $\mathbf{R}$ are true but $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A...

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The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom

Question: The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to $\frac{\mathrm{h}^{2}}{\mathrm{xma}_{0}^{2}}$. The value of $10 x$ is______________ ( $\mathrm{a}_{0}$ is radius of Bohr's orbit) (Nearest integer) [Given : $\pi=3.14]$ Solution: $\mathrm{mvr}=\frac{\mathrm{nh}}{2 \pi}$ K.E. $=\frac{\mathrm{n}^{2} \mathrm{~h}^{2}}{8 \pi^{2} \mathrm{mr}^{2}}=\frac{4 \mathrm{~h}^{2}}{8 \pi^{2} \mathrm{~m}\left(4 \mathrm{a}_{0}\right)^{2}}$ $=\left(\frac{4}{8 \pi^{2}...

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The difference between bond orders of

Question: The difference between bond orders of $\mathrm{CO}$ and $\mathrm{NO}^{\oplus}$ is $\frac{\mathrm{x}}{2}$ where $\mathrm{x}=$___________. (Round off to the Nearest Integer) Solution: Bond order of $\mathrm{CO}=3$ Bond order of $\mathrm{NO}^{+}=3$ Difference $=0=\frac{x}{2}$ $x=0$...

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Given below are two statements: one is labelled as

Question: Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) : Assertion (A) : A simple distillation can be used to separate a mixture of propanol and propanone. Reason (R) : Two liquids with a difference of more than $20^{\circ} \mathrm{C}$ in their boiling points can be separated by simple distillations. In the light of the above statements, choose the most appropriate answer from the options given below :(A) is false but (R) is true.Both ...

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For water at 100°C and 1 bar,

Question: For water at $100^{\circ} \mathrm{C}$ and $1 \mathrm{bar}$, $\Delta_{\text {vap }} \mathrm{H}-\Delta_{\text {vap }} \mathrm{U}=\ldots 10^{2} \mathrm{~J} \mathrm{~mol}^{-1}$ (Round off to the Nearest Integer) [Use : $\mathrm{R}=8.31 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$ ] [Assume volume of $\mathrm{H}_{2} \mathrm{O}(\mathrm{l})$ is much smaller than volume of $\mathrm{H}_{2} \mathrm{O}(\mathrm{g})$. Assume $\mathrm{H}_{2} \mathrm{O}(\mathrm{g})$ treated as an ideal gas] Solut...

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The species given below that does NOT show

Question: The species given below that does NOT show disproportionation reaction is :$\mathrm{BrO}_{4}^{-}$$\mathrm{BrO}^{-}$$\mathrm{BrO}_{2}^{-}$$\mathrm{BrO}_{3}^{-}$Correct Option: 1 Solution: In $\mathrm{BrO}_{4}^{\ominus}, \mathrm{Br}$ is in highest oxidation state $(+7)$, So it cannot oxidise further hence it cannot show disproportionation reaction....

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At 298.2 K the relationship between

Question: At $298.2 \mathrm{~K}$ the relationship between enthalpy of bond dissociation (in $\mathrm{kJ} \mathrm{mol}^{-1}$ ) for hydrogen $\left(\mathrm{E}_{\mathrm{H}}\right)$ and its isotope, deuterium $\left(E_{D}\right)$, is best described by:$\mathrm{E}_{\mathrm{H}}=\frac{1}{2} \mathrm{E}_{\mathrm{D}}$$\mathrm{E}_{\mathrm{H}}=\mathrm{E}_{\mathrm{D}}$$\mathrm{E}_{\mathrm{H}} \simeq \mathrm{E}_{\mathrm{D}}-7.5$$E_{H}=2 E_{D}$Correct Option: , 3 Solution: Enthalpy of bond dissociation (kJ/mol...

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The reaction that occurs in a breath analyser, a device used to determine the alcohol level in a person's blood stream is

Question: The reaction that occurs in a breath analyser, a device used to determine the alcohol level in a person's blood stream is $2 \mathrm{~K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+8 \mathrm{H}_{2} \mathrm{SO}_{4}+3 \mathrm{C}_{2} \mathrm{H}_{6} \mathrm{O} \rightarrow 2 \mathrm{Cr}_{2}\left(\mathrm{SO}_{4}\right)_{3}+$ $3 \mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{2}+2 \mathrm{~K}_{2} \mathrm{SO}_{4}+11 \mathrm{H}_{2} \mathrm{O}$ If the rate of appearance of $\mathrm{Cr}_{2}\left(\mathrm{SO}_{4}...

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In gaseous triethyl amine

Question: In gaseous triethyl amine the "-C-N-C-" bond angle is__________ degree. Solution: In gaseous triethyl amine the "-C-N-C-" bond angle is 108 degree....

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The water soluble protein is :

Question: The water soluble protein is :FibrinAlbuminMyosinCollagenCorrect Option: , 2 Solution: Albumin is water soluble....

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The number of geometrical isomers possible in triamminetrinitrocobalt

Question: The number of geometrical isomers possible in triamminetrinitrocobalt (III) is $\mathrm{X}$ and in trioxalatochromate (III) is Y. Then the value of $\mathrm{X}+\mathrm{Y}$ is___________. Solution: Triamminetrinitrocobalt(III) $\rightarrow\left[\mathrm{Co}\left(\mathrm{NO}_{2}\right)_{3}\left(\mathrm{NH}_{3}\right)_{3}\right]$ trioxalatochromate(III) ion $\rightarrow\left[\mathrm{Cr}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{3}\right]^{3-}$ $\left[\mathrm{Co}\left(\mathrm{NO}_{2}\right...

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In Carius method for estimation of halogens, 0.2 g of an organic compound gave 0.188 g of AgBr.

Question: In Carius method for estimation of halogens, 0.2 g of an organic compound gave 0.188 g of AgBr. The percentage of bromine in the compound is ________ . (Nearest integer) [Atomic mass : $\mathrm{Ag}=108, \mathrm{Br}=80]$ Solution: $\mathrm{n}_{\mathrm{AgBr}}=\frac{0.188 \mathrm{~g}}{188 \mathrm{~g} / \mathrm{mol}}=10^{-3} \mathrm{~mol}$ $\Rightarrow \mathrm{n}_{\mathrm{Br}}=\mathrm{n}_{\mathrm{AgBr}}=0.001 \mathrm{~mol}$ $\Rightarrow$ mass $_{\mathrm{Br}}=(0.001 \times 80) \mathrm{gm}=0...

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