Match List-I with List - II :

Question: Match List-I with List - II : Choose the most appropriate answer from the options given below : (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)(a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)(a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)(a)-(iii), (b)-(ii), (c)-(iv), (d)-(i)Correct Option: 1 Solution: (Name of ore/mineral)...

Read More →

An LPG cylinder contains gas

Question: An LPG cylinder contains gas at a pressure of 300 $\mathrm{kPa}$ at $27^{\circ} \mathrm{C}$. The cylinder can withstand the pressure of $1.2 \times 10^{6} \mathrm{~Pa}$. The room in which the cylinder is kept catches fire. The minimum temperature at which the bursting of cylinder will take place is___________ ${ }^{\circ} \mathrm{C}$. (Nearest integer) Solution: $\frac{\mathrm{P}_{1}}{\mathrm{~T}_{1}}=\frac{\mathrm{P}_{2}}{\mathrm{~T}_{2}} \Rightarrow \frac{300 \times 10^{3}}{300}=\fra...

Read More →

Which one of the following pairs of isomers

Question: Which one of the following pairs of isomers is an example of metamerism ?Correct Option: , 4 Solution:...

Read More →

When 3.00 g of a substance

Question: When $3.00 \mathrm{~g}$ of a substance ' $\mathrm{X}$ ' is dissolved in $100 \mathrm{~g}$ of $\mathrm{CCl}_{4}$, it raises the boiling point by $0.60 \mathrm{~K}$. The molar mass of the substance ' $\mathrm{X}^{\prime}$ is g $\mathrm{mol}^{-1}$. (Nearest integer). $\left[\right.$ Given $\mathrm{K}_{\mathrm{b}}$ for $\mathrm{CCl}_{4}$ is $\left.5.0 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$ Solution: $\Delta \mathrm{T}_{\mathrm{b}}=\mathrm{K}_{\mathrm{b}} \times$ molality $0.60...

Read More →

Hydrolysis of sucrose gives :

Question: Hydrolysis of sucrose gives :$\alpha-\mathrm{D}-(-)-$ Glucose and $\beta-\mathrm{D}-(-)-$ Fructose$\alpha-\mathrm{D}-(+)$-Glucose and $\alpha-\mathrm{D}-(-)$-Fructose$\alpha-\mathrm{D}-(-)-$ Glucose and $\alpha-\mathrm{D}-(+)-$ Fructose$\alpha-D-(+)-$ Glucose and $\beta-D-(-)$-FructoseCorrect Option: , 4 Solution: Sucrose is formed by $\alpha-\mathrm{D}(+)$. Glucose $+\beta-\mathrm{D}(-)$ Fructose. we obtain these monomers on hydrolysis....

Read More →

0.8 g of an organic compound was

Question: $0.8 \mathrm{~g}$ of an organic compound was analysed by Kjeldahl's method for the estimation of nitrogen. If the percentage of nitrogen in the compound was found to be $42 \%$, then $\mathrm{mL}$ of $1 \mathrm{M}$ $\mathrm{H}_{2} \mathrm{SO}_{4}$ would have been neutralized by the ammonia evolved during the analysis. Solution: Organic compound : $0.8 \mathrm{gm}$ wt. of $\mathrm{N}=\left(\frac{42}{100} \times 0.8\right) \mathrm{gm}$ mole of $\mathrm{N}=\frac{42 \times 0.8}{100 \times ...

Read More →

Match List-I with List-II :

Question: Match List-I with List-II : Choose the most appropriate answer from the options given below:(a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)(a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)(a)-(i), (b)-(iv), (c)-(ii), (d)-(iii)(a)-(iv), (b)-(ii), (c)-(iii), (d)-(i)Correct Option: , 2 Solution: $\mathrm{Mn}^{2+} \rightarrow$ III group $\mathrm{As}^{3+} \rightarrow \mathrm{II} \mathrm{B}$ group $\mathrm{Cu}^{2+} \rightarrow$ II A group $\mathrm{Al}^{3+} \rightarrow$ IV group...

Read More →

Which one of the following tests used for the identification of functional groups in organic compounds does not use copper reagent ?

Question: Which one of the following tests used for the identification of functional groups in organic compounds does not use copper reagent ?Barfoed's testSeliwanoff's testBenedict's testBiuret test for peptide bondCorrect Option: , 2 Solution: In Seliwanoff's reagent, Cu is not present. In Barfoed, Biuret and in Benediet reagent Cu is present....

Read More →

Assuming that

Question: Assuming that $\mathrm{Ba}(\mathrm{OH})_{2}$ is completely ionised in aqueous solution under the given conditions the concentration of $\mathrm{H}_{3} \mathrm{O}^{+}$ions in $0.005 \mathrm{M}$ aqueous solution of $\mathrm{Ba}(\mathrm{OH})_{2}$ at $298 \mathrm{~K}$ is___________$\times 10^{-12}$ mol $\mathrm{L}^{-1}$. (Nearest integer) Solution: At $298 \mathrm{~K}$ : in aq. solution $\left[\mathrm{H}_{3} \mathrm{O}^{+}\right][\mathrm{OH}]=10^{-14}$ $\left[\mathrm{H}_{3} \mathrm{O}^{+}\...

Read More →

Which one of the following correctly represents the

Question: Which one of the following correctly represents the order of stability of oxides, $\mathrm{X}_{2} \mathrm{O} ;(\mathrm{X}=$ halogen $) ?$ $\mathrm{Br}\mathrm{Cl}\mathrm{I}$$\mathrm{Br}\mathrm{I}\mathrm{Cl}$$\mathrm{Cl}\mathrm{I}\mathrm{Br}$$\mathrm{I}\mathrm{Cl}\mathrm{Br}$Correct Option: , 4 Solution: Stability of oxides of Halogens is $\mathrm{I}\mathrm{Cl}\mathrm{Br}$...

Read More →

The number of significant figures

Question: The number of significant figures in $0.00340$ is____________. Solution: Number of significant figures $=3$...

Read More →

For a chemical reaction

Question: For a chemical reaction $\mathrm{A} \rightarrow \mathrm{B}$, it was found that concentration of $\mathrm{B}$ is increased by $0.2 \mathrm{~mol} \mathrm{~L}^{-1}$ in 30 min. The average rate of the reaction is _____________$\times 10^{-1} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~h}^{-1}$. (in nearest integer) Solution: Av. rate of reaction $=-\frac{\Delta[\mathrm{A}]}{\Delta \mathrm{t}}=\frac{\Delta[\mathrm{B}]}{\Delta \mathrm{t}}=\frac{(0.2-0)}{\frac{1}{2}}$ $=0.4=4 \times 10^{-1} \math...

Read More →

Potassium permanganate on heating at 513 K gives a product which is :

Question: Potassium permanganate on heating at 513 K gives a product which is :paramagnetic and colourlessdiamagnetic and greendiamagnetic and colourlessparamagnetic and greenCorrect Option: , 4 Solution: In $\mathrm{K}_{2} \mathrm{Mn} \mathrm{O}_{4}$, manganese oxidation state is $+6$ and hence it has one unpaired $\mathrm{e}^{-} .$...

Read More →

Which among the following is not a polyester?

Question: Which among the following is not a polyester?NovolacPHBVDacronGlyptalCorrect Option: 1 Solution: Novalac is a linear polymer of $[\mathrm{Ph}-\mathrm{OH}+\mathrm{HCHO}]$. So ester linkage not present. So novalac is not a polyester....

Read More →

Solve this

Question: Consider the above chemical reaction. The total number of stereoisomers possible for Product ' $\mathrm{P}$ ' is______ Solution: The total number of products possible $=2$...

Read More →

Which one of the following statements is incorrect?

Question: Which one of the following statements is incorrect?Atomic hydrogen is produced when $\mathrm{H}_{2}$ molecules at a high temperature are irradiated with UV radiation.At around $2000 \mathrm{~K}$, the dissociation of dihydrogen into its atoms is nearly $8.1 \%$.Bond dissociation enthalpy of $\mathrm{H}_{2}$ is highest among diatomic gaseous molecules which contain a single bond.Dihydrogen is produced on reacting zine with $\mathrm{HCl}$ as well as $\mathrm{NaOH}_{\text {(aa) }}$.Correct...

Read More →

Number of electrons present

Question: Number of electrons present in $4 \mathrm{f}$ orbital of $\mathrm{Ho}^{3+}$ ion is . (Given Atomic No. of Ho $=67$ ) Solution: $\mathrm{Ho}=[\mathrm{Xe}] 4 \mathrm{f}^{11} 6 \mathrm{~s}^{2}$ $\mathrm{Ho}^{3+}=[\mathrm{Xe}] 4 \mathrm{f}^{10}$ so number of $\mathrm{e}^{-}$present in $4 \mathrm{f}$ is 10 ....

Read More →

The major product of the following reaction,

Question: The major product of the following reaction, if it occurs by $\mathrm{S}_{\mathrm{N}} 2$ mechanism is : Correct Option: , 4 Solution:...

Read More →

At 20°C, the vapour pressure of benzene is 70

Question: At $20^{\circ} \mathrm{C}$, the vapour pressure of benzene is 70 torr and that of methyl benzene is 20 torr. The mole fraction of benzene in the vapour phase at $20^{\circ} \mathrm{C}$ above an equimolar mixture of benzene and methyl benzene is ________$\times 10^{-2}$. (Nearest integer) Solution: $\mathrm{P}_{\mathrm{B}}^{\mathrm{o}}=40$$\mathrm{P}_{\mathrm{T}}^{\mathrm{o}}=20$$\mathrm{K}_{\mathrm{B}}=0.5=\mathrm{K}_{\mathrm{T}}$ Now $\quad \mathrm{y}_{\mathrm{B}}=\frac{\mathrm{K}_{\m...

Read More →

An accelerated electron has

Question: An accelerated electron has a speed of $5 \times 10^{6} \mathrm{~ms}^{-1}$ with an uncertainty of $0.02 \%$. The uncertainty in finding its location while in motion is $\times \times 10^{-9} \mathrm{~m}$. The value of $x$ is ____________(Nearest integer) [Use mass of electron $=9.1 \times 10^{-31} \mathrm{~kg}$,$\left.\mathrm{h}=6.63 \times 10^{-34} \mathrm{Js}, \pi=3.14\right]$ Solution: $\Delta \mathrm{v}=\frac{0.02}{100} \times 5 \times 10^{6}=10^{3} \mathrm{~m} / \mathrm{s}$ $\Delt...

Read More →

The incorrect expression among the following is:

Question: The incorrect expression among the following is:$\frac{\Delta \mathrm{G}_{\text {System }}}{\Delta \mathrm{S}_{\text {Total }}}=-\mathrm{T}($ at constant $\mathrm{P})$$\ln \mathrm{K}=\frac{\Delta \mathrm{H}^{\circ}-\mathrm{T} \Delta \mathrm{S}^{\circ}}{\mathrm{RT}}$$\mathrm{K}=\mathrm{e}^{-\Delta \mathrm{G}^{\circ} / \mathrm{RT}}$For isothermal process $\mathrm{w}_{\text {reversible }}=-\mathrm{nRT} \ln \frac{\mathrm{V}_{f}}{\mathrm{~V}_{i}}$Correct Option: , 2 Solution: Option (2) is ...

Read More →

Lyophilic sols are more stable than lyophobic sols because :

Question: Lyophilic sols are more stable than lyophobic sols because :there is a strong electrostatic repulsion the colloidal particles have positive charge. between the negatively charged colloidal particles.the colloidal particles have positive chargethe colloidal particles have no charge.the colloidal particles are solvatedCorrect Option: , 4 Solution: In the lyophilic colloids, the colloidal particles are extensively solvated....

Read More →

A system does

Question: A system does $200 \mathrm{~J}$ of work and at the same time absorbs $150 \mathrm{~J}$ of heat. The magnitude of the change in internal energy is_______J. (Nearest integer) Solution: $\mathrm{w}=-200 \mathrm{~J}, \mathrm{q}=+150: \Delta \mathrm{U}=\mathrm{q}+\mathrm{w}$ $\Delta U=150-200=-50 J:$ magnitude $=50 J=|\Delta U|$...

Read More →

For the cell

Question: For the cell $\mathrm{Cu}(\mathrm{s})\left|\mathrm{Cu}^{2+}(\mathrm{aq})(0.1 \mathrm{M}) \| \mathrm{Ag}^{+}(\mathrm{aq})(0.01 \mathrm{M})\right| \mathrm{Ag}(\mathrm{s})$ the cell potential $\mathrm{E}_{1}=0.3095 \mathrm{~V}$ For the cell $\mathrm{Cu}(\mathrm{s})\left|\mathrm{Cu}^{2+}(\mathrm{aq})(0.01 \mathrm{M}) \| \mathrm{Ag}^{+}(\mathrm{aq})(0.001 \mathrm{M})\right| \mathrm{Ag}(\mathrm{s})$ the cell potential = $\times 10^{-2} \mathrm{~V}$. (Round off the Nearest Integer). $\left[\r...

Read More →

An average person needs about 10000 kJ energy per day.

Question: An average person needs about $10000 \mathrm{~kJ}$ energy per day. The amount of glucose (molar mass $=180.0 \mathrm{~g} \mathrm{~mol}^{-1}$ ) needed to meet this energy requirement is _________g. (Use : $\Delta_{\mathrm{C}} \mathrm{H}$ (glucose) $=-2700 \mathrm{~kJ} \mathrm{~mol}^{-1}$ ) Solution: 1 mole glucose give 2700 kJ energy so mole of glucose needed for $10^{5} \mathrm{~kJ}$ energy $=\frac{10000}{2700}=370 \mathrm{moles}$ wt. of glucose $=3.10 \times 180$ $=666.666$ $\approx 6...

Read More →