Prove the following
Question: Considering the above reaction, $X$ and $Y$ respectively are:Correct Option: , 2 Solution:...
Read More →Given below are two statements : one is labelled as Assertion
Question: Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason $\mathbf{R}$ : Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below :$\mathbf{A}$ is true but $\mathbf{R}$ is falseBoth $\mathbf{A}$ and $\mathbf{R}$ are true and $\mathbf{R}$ is th...
Read More →Among the following, the aromatic compounds are :
Question: Among the following, the aromatic compounds are : \ Choose the correct answer from the following options :(A) and (B) only(B) and (C) only(B), (C) and (D) only(A), (B) and (C) onlyCorrect Option: , 2 Solution: (A) Non-Aromatic (B) Aromatic (C) Aromatic (D) Anti-Aromatic...
Read More →A central atom in a molecule has two lone pairs of electrons and forms three single bonds. The shape of this molecule is:
Question: A central atom in a molecule has two lone pairs of electrons and forms three single bonds. The shape of this molecule is: see-sawplanar triangularT-shapedtrigonal pyramidalCorrect Option: , 3 Solution: $\mathrm{sp}^{3} \mathrm{~d}$ hybridised T-shaped...
Read More →Given below are two statements : one is labelled as Assertion
Question: Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason $\mathbf{R}$ : Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below :$\mathbf{A}$ is true but $\mathbf{R}$ is falseBoth $\mathbf{A}$ and $\mathbf{R}$ are true and $\mathbf{R}$ is th...
Read More →Solve this following
Question: The product "A" in the above reaction is: Correct Option: , 2 Solution:...
Read More →The correct shape and I-I-I bond angles respectively
Question: The correct shape and I-I-I bond angles respectively in $\mathrm{I}_{3}^{-}$ion are :-Distorted trigonal planar; $135^{\circ}$ and $90^{\circ}$T-shaped; $180^{\circ}$ and $90^{\circ}$Trigonal planar; $120^{\circ}$Linear; $180^{\circ}$Correct Option: 4, Solution: Shape : Linear, I-I-I Bond angle $\Rightarrow 180$...
Read More →The pH of ammonium phosphate solution,
Question: The $\mathrm{pH}$ of ammonium phosphate solution, if $\mathrm{pK}_{\mathrm{a}}$ of phosphoric acid and $\mathrm{pk}_{\mathrm{b}}$ of ammonium hydroxide are $5.23$ and $4.75$ respectively, is_________. Solution: Since $\left(\mathrm{NH}_{4}\right)_{3} \mathrm{PO}_{4}$ is salt of weak acid $\left(\mathrm{H}_{3} \mathrm{PO}_{4}\right)$ \ weak base $\left(\mathrm{NH}_{4} \mathrm{OH}\right)$. $\mathrm{pH}=7+\frac{1}{2}(\mathrm{pka}-\mathrm{pkb})$ $=7+\frac{1}{2}(5.23-4.75)$ $=7.24 \approx 7...
Read More →If the activation energy of a reaction is
Question: If the activation energy of a reaction is $80.9 \mathrm{~kJ}$ $\mathrm{mol}^{-1}$, the fraction of molecules at $700 \mathrm{~K}$, having enough energy to react to form products is $\mathrm{e}^{-x}$. The value of $x$ is____________. (Rounded off to the nearest integer) [Use $R=8.31 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$ ] Solution: Fraction of molecules to have enough energy to react $=e^{-E a / R T}$ So, $x=\frac{E_{\mathrm{a}}}{R T}$ $=\frac{80.9 \times 10^{3}}{8.31 \times ...
Read More →Match List-I with List-II :
Question: Match List-I with List-II : Choose the correct answer from the options given below:(a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)(a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)(a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)(a)-(iv), (b)-(i), (c)-(ii), (d)-(iii)Correct Option: , 3 Solution: (a) Haber's process is used for $\mathrm{NH}_{3}$ synthesis. (b) Ostwald's process is used for $\mathrm{HNO}_{3}$ synthesis. (c) Contact process is used for $\mathrm{H}_{2} \mathrm{SO}_{4}$ synthesis. (d) In Hall-Heroult proc...
Read More →Which of the following is an aromatic compound?
Question: Which of the following is an aromatic compound? Correct Option: 1 Solution:...
Read More →The number of stereoisomers possible for
Question: The number of stereoisomers possible for $\left[\mathrm{Co}(\mathrm{ox})_{2}(\mathrm{Br})\left(\mathrm{NH}_{3}\right)\right]^{2-}$ is________ . $[\mathrm{ox}=$ oxalate $]$ Solution: Total number of stereoisomers in $\left[\mathrm{Co}(\mathrm{ox})_{2} \mathrm{Br}\left(\mathrm{NH}_{3}\right)\right]^{2 \mathrm{O}}$ i.e. $\simeq\left[\mathrm{M}(\mathrm{AA})_{2} \mathrm{ab}\right]^{2-}$ $\rightarrow$ cis is optically active isomers and trans is optically inactive isomer $\rightarrow$ Hence ...
Read More →The incorrect statement among
Question: The incorrect statement among the following is :-$\mathrm{VOSO}_{4}$ is a reducing agent$\mathrm{Cr}_{2} \mathrm{O}_{3}$ is an amphoteric oxide$\mathrm{RuO}_{4}$ is an oxidizing agentRed colour of ruby is due to the presence of $\mathrm{Co}^{3+}$Correct Option: 4, Solution: (i) In $\mathrm{VOSO}_{4}$, ' $\mathrm{V}$ ' is in $+4$ oxidation state. So it act as oxidising agent. (ii) $\mathrm{Cr}_{2} \mathrm{O}_{3}$ is an amphoteric oxide. (iii) In $\mathrm{RuO}_{4}$, ' $\mathrm{Ru}$ ' is ...
Read More →With respect to drug-enzyme interaction, identify the wrong statement:
Question: With respect to drug-enzyme interaction, identify the wrong statement: Non-Competitive inhibitor binds to the allosteric siteAllosteric inhibitor changes the enzyme's active siteAllosteric inhibitor competes with the enzyme's active siteCompetitive inhibitor binds to the enzyme's active siteCorrect Option: , 3 Solution: Some durg do not bind to the Enzyme's active site. These bind to a different site of enzyme which called allosteric site. This binding of inhibitor at allosteric site c...
Read More →In mildly alkaline medium,
Question: In mildly alkaline medium, thiosulphate ion is oxidized by $\mathrm{MnO}_{4}^{-}$to "A". The oxidation state of sulphur in "A" is_______. Solution: $\mathrm{MnO}_{4}^{-}+\mathrm{S}_{2} \mathrm{O}_{3}^{2-} \rightarrow \mathrm{MnO}_{2}+\underset{(\mathrm{A})}{\mathrm{SO}_{4}^{2-}}$ Oxidation state of ' $\mathrm{S}$ ' in $\mathrm{SO}_{4}{ }^{2-}$ $=+6$...
Read More →Solve the Following Questions
Question: The product "P" in the above reaction is :Correct Option: , 2 Solution: DIBAL can not reduce double bond It can reduce cyclic ester....
Read More →The number of octahedral voids per lattice site
Question: The number of octahedral voids per lattice site in a lattice is_________ .(Rounded off to the nearest integer) Solution: If number of lattice points are $\mathrm{N}$. then effective octahedral voids $=\mathrm{N}$ So, octahedral voids / lattice site $=1$...
Read More →A ball weighing 10g is moving with a velocity of
Question: A ball weighing $10 \mathrm{~g}$ is moving with a velocity of $90 \mathrm{~ms}^{-1}$. If the uncertainty in its velocity is $5 \%$, then the uncertainty in its position is__________ $\times 10^{-33} \mathrm{~m}$. (Rounded off to the nearest integer) $\left[\right.$ Given : $\left.\mathrm{h}=6.63 \times 10^{-34} \mathrm{Js}\right]$ Solution: $\Delta \mathrm{v}=90 \times \frac{5}{100}$ $=4.5 \mathrm{~m} / \mathrm{s}$ $\Delta \mathrm{v} . \Delta \mathrm{x}=\frac{\mathrm{h}}{4 \pi \mathrm{...
Read More →Given below are two statements :-
Question: Given below are two statements :- Statement I : The value of the parameter "Biochemical Oxygen Demand (BOD)" is important for survival of aquatic life. Statement II : The optimum value of BOD is $6.5 \mathrm{ppm}$. In the light of the above statements, choose the most appropriate answer from the options given below :Statement I is false but Statement II is trueBoth Statement I and Statement II are trueStatement I is true but Statement II is falseBoth Statement I and Statement II are fa...
Read More →Given below are two statements :
Question: Given below are two statements : Statement $\mathrm{I}:$ Both $\mathrm{CaCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}$ and $\mathrm{MgCl}_{2} \cdot 8 \mathrm{H}_{2} \mathrm{O}$ undergo dehydration on heating. Statement II : $\mathrm{BeO}$ is amphoteric whereas the oxides of other elements in the same group are acidic In the light of the above statements, choose the correct answer from the options given below :Statement I is false but statement II is trueBoth statement I and statement II a...
Read More →The average S-F bond energy in
Question: The average S-F bond energy in $\mathrm{kJ} \mathrm{mol}^{-1}$ of $\mathrm{SF}_{6}$ is_________. (Rounded off to the nearest integer) [Given : The values of standard enthalpy of formation of $S F_{6}(g), S(g)$ and $F(g)$ are $-1100$, 275 and $80 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively.] Solution: $\mathrm{SF}_{6}(\mathrm{~g}) \rightarrow \mathrm{S}(\mathrm{g})+6 \mathrm{~F}(\mathrm{~g})$ If $\in$ - bond enthalpy $\Delta_{\mathrm{r}} \mathrm{H}=6 \times \epsilon_{\mathrm{S}-\mathr...
Read More →What is the correct order of the following
Question: What is the correct order of the following elements with respect to their density ?$\mathrm{Cr}\mathrm{Zn}\mathrm{Co}\mathrm{Cu}\mathrm{Fe}$$\mathrm{Zn}\mathrm{Cu}\mathrm{Co}\mathrm{Fe}\mathrm{Cr}$$\mathrm{Zn}\mathrm{Cr}\mathrm{Fe}\mathrm{Co}\mathrm{Cu}$$\mathrm{Cr}\mathrm{Fe}\mathrm{Co}\mathrm{Cu}\mathrm{Zn}$Correct Option: 3, Solution:...
Read More →When 12.2 g of benzoic acid is dissolved in 100g of water,
Question: When $12.2 \mathrm{~g}$ of benzoic acid is dissolved in $100 \mathrm{~g}$ of water, the freezing point of solution was found to be $-0.93^{\circ} \mathrm{C}\left(\mathrm{K}_{f}\left(\mathrm{H}_{2} \mathrm{O}\right)=1.86 \mathrm{~K} \mathrm{~kg}\right.$ $\mathrm{mol}^{-1}$ ). The number $(\mathrm{n})$ of benzoic acid molecules associated (assuming $100 \%$ association) is_____. Solution: $\Delta \mathrm{T}_{\mathrm{f}}=\mathrm{i} \times \mathrm{k}_{\mathrm{f}} \times \mathrm{m}$ $0-(-0....
Read More →Solve this following
Question: If $\mathrm{A}=\left[\begin{array}{lll}1 1 1 \\ 0 1 1 \\ 0 0 1\end{array}\right]$ and $\mathrm{M}=\mathrm{A}+\mathrm{A}^{2}+\mathrm{A}^{3}+\ldots .+\mathrm{A}^{20}$ then the sum of all the elements of the matrix $M$ is equal to____________ Solution: $A^{n}=\left[\begin{array}{ccc}1 n \frac{n^{2}+n}{2} \\ 0 1 n \\ 0 0 1\end{array}\right]$ So, required sum $=20 \times 3+2 \times\left(\frac{20 \times 21}{2}\right)+\sum_{\mathrm{r}=1}^{20}\left(\frac{\mathrm{r}^{2}+\mathrm{r}}{2}\right)$ $...
Read More →Which one of the following
Question: Which one of the following compounds is nonaromatic ?Correct Option: 1, Solution: For the following ion/compounds...
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