Read the passage given below and answer the following questions F… - Vidyadip

Question

Read the passage given below and answer the following questions
Few colligative properties are:

Relative lowering of vapour pressure: depends only on molar concentration of solute $($mole fraction$)$ and independent of its nature.
Depression in freezing point: it is proportional to the molal concentration of solution.
Elevation of boiling point: it is proportional to the molal concentration of solute.
Osmotic pressure: it is proportional to the molar concentration of solute

A solution of glucose is prepared with $0.052 g$ at glucose in $80.2 g$ of water.$(KJ = 1.86K \ \text{kg \ mol}^{-1}$ and $K_b = 5.2K \ \text{kg \ mol}^{-1})$
The following questions are multiple choice questions. Choose the most appropriate answer:

Molality of the given solution is.

$0.0052m$
$0.0036m$
$0.0006m$
$1.29m$

Boiling point for the solution will be.

$373.05K$
$373.15K$
$373.02K$
$373.02K$

The depression in freezing point of solution will be.

$0.0187K$
$0.035K$
$0.082K$
$0.067K$

Mole fraction of glucose in the given solution is.

$6.28 \times 10^{-5}$
$6.28 \times 10^{-4}$
$0.00625$
$0.00028$

If same amount of sucrose $\ce{(C_{12} H_{22} O_{11})}$ is taken instead of glucose, then.

Elevation in boiling point will be higher.
Depression in freezing point will be higher.
Depression in freezing point will be lower.
Both $(a)$ and $(b).$

✓

Answer

$(b) \ 0.0036\ m$

$\text{m}=\frac{0.052}{180}\times\frac{1000}{80.2}=0.0036$

$(c) \ 373.02K$

$\Delta\text{T}_\text{b}=\text{k}_\text{b}\times\text{m}=5.2\times0.0036=0.0187\ \text{K}$
$T_b = 373 + 0.0187 = 373.0187 K $ approx $ 373.02 K$

$(d)\ 0.067 K$

$\Delta\text{T}_\text{f}=\text{k}_\text{f}\times\text{m}=1.86\times0.0036=0.067\ \text{K}$

$(a) \ 6.28 \times 10^{-5}$

Moles of water $\frac{80.2}{18}=4.455$
Mole fraction of glucose $=\frac{0.00028}{4.45+0.00028}=6.28\times10^{-5}$

$(c)$ Depression in freezing point will be lower.

Depression in freezing point or elevation in boiling point is proportional to molarity, which is proportional to number of moles.
For same amount, higher the molar mass of solute, lower will be number of moles.
Hence, lower will be the colligative property.

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First member of ketos sugar is:

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Ketotetrose.
Ketopentose.
Ketohexose.

In $\ce{CH_2OHCHOHCHOHCHOHCHOHCHO,}$ the number of optical isomers will be:

$16$
$8$
$32$
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Glucose is aldohexose.
Naturally occurring glucose is dextrorotatory.
Glucose contains three chiral centres.
Glucose contains one $1^\circ $ alcoholic group and four $2^\circ$ alcoholic groups.

Among the above, correct statements are:

$1$ and $2$ only
$3$ and $4$ only
$1, 2$ and $4$ only
$1, 2, 3$ and $4$

Two hexoses fonn the same osazone, find the correct statement about these hexoses.

Both of them must be aldoses.
They are epimers at $C-3.$
The carbon atoms $I$ and $2$ in both have the same configuration.
The carbon atoms $3, 4$ and $5$ in both have the same configuration.

Which of the following reactions of glucose can be explained only by its cyclic structure?

Glucose forms cyanohydrin with $\text{HCN}.$
Glucose reacts with hydroxylamine to form an oxime.
Pentaacetate of glucose does not react with hydroxylamine.
Glucose is oxidised by nitric acid to gluconic acid.

For a reaction, $A + B \rightarrow$ Products, the rate law is $-$ Rate $= k[A][B]^{3/2}$ Can the reaction be an elementary reaction? Explain.

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Coordination compounds are formulated and named according to the $\text{IUPAC}$ system.
Few rules for naming coordination compounds are:

In ionic complex, the cation is named first and then the anion.
In the coordination entity, the ligands are named first and then the central metal ion.
When more than one type of ligands are present, they are named in alphabetical order of preference without any consideration of charge.

The following questions are multiple choice questions. Choose the most appropriate answer:

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Triamminechlorobromonitroplatinum $(IV)$ chloride.
Triamminebromonitrochloroplatinum $(IV)$ chloride.
Triamminebromidochloridonitroplatinum $(IV)$ chloride.
Triamminenitrochlorobromoplatinum $(IV)$ chloride.

The $\text{IUPAC}$ name of $\ce{[Ni(CO)_4]}$ is:

Tetracarbonylnickel $(II).$
Tetracarbonylnickel $(0).$
Tetracarbonylnickelate $(II).$
Tetracarbonylnickelate $(0).$

As per $\text{IUPAC}$ nomenclature, the name of the complex $\ce{[Co(H_2O)_4(NH_3)_2]Cl_3}$ is:

Tetraaquadiamminecobalt $(II)$ chloride.
Tetraaquadiamminecobalt $(III)$ chloride.
Diamminetetraaquacobalt $(II)$ chloride.
Diamminetetraaquacobalt $(III)$ chloride.

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$\ce{[CoCl_2(en)]^+}$
$\ce{[CoCl_2(en)_2]^+}$

Correct formula of pentaamminenitro$-O-$cobalt $(III)$ sulphate is:

$\ce{[Co(NO_2)(NH_3)_5]SO_4}$
$\ce{[Co(ONO)(NH_3)_5]SO_4}$
$\ce{[Co(NO_2)(NH_3)_4](SO_4)_2}$
$\ce{[Co(ONO)(NH_3)_4](SO_4)_2}$

Describe detailed information on classification of carbohydrates.

Read the passage given below and answer the following questions:
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The $d-$orbitals involved in the hybridisation may be either inner $d-$orbitals i.e.$, (n - 1)d$ or outer $d-$orbitals i.e.$, nd.$
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It is paramagnetic.
It has coordination number of $6.$
It is outer orbital complex.
It involves $d^2sp^3$ hybridisation.

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$3\text{d}^1_\text{xy},3\text{d}^1_{\text{yz}},3\text{d}^1_\text{zx}$
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It is an octahedral, di magnetic and outer orbital complex.
It is an octahedral, paramagnetic and outer orbital complex.
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It is an octahedral, di magnetic and inner orbital complex.

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$3$ electrons.
$4$ electrons.
$2$ electrons.
$1$ electron.

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$[\ce{Ni(H2O)6}]^{3+}$
$[\ce{FeF6}]^{3-}$
$[\ce{Co(CN)6}]^{3-}$
$[\ce{NiCl4}]^{2-}$

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The following questions are multiple choice questions. Choose the most appropriate answer :

The unit of rate constant for a first order reaction is:

$S^{-1}$
$mol\ L^{-1} s^{-1}$
$L\ mol^{-1} s^{-1}$
$L^2\ mol^{-2} s^{-1}$

Half$-$life period of a first order reaction is $10$ min. Starting with initial concentration $12M,$ the rate after $20$ min is:

$0.693 \times 3M\ min^{-1}$
$0.0693 \times 4M\ min^{-1}$
$0.0693 \times M\ min^{-1}$
$0.0693 \times 3M\ min^{-1}$

$50\%$ of a first order reaction is complete in $23$ minutes. Calculate the ti me required to complete $90\%$ of the reaction.

$70.4$ minutes.
$76.4$ minutes.
$38.7$ minutes.
$35.2$ minutes.

For a first order reaction$, (A) \rightarrow$ products, the concentration of $A$ changes from $0.1M$ to $0.025M$ in $40$ minutes. The rate of reaction when the concentration of $A$ is $0.01M,$ is:

$3.47 \times 10^{-4} M/ min$
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$1.73 \times 10^{-5} M/ min$

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$6.25\%$
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Epimers.
Enantiomers.
Anomers.
Conformational diasteriomers.

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$D-$type.
$L-$type.
Both of these.
None of these.

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$-\ce{OH}$ and $-\ce{COOH}$
$-\ce{CHO}$ and $-\ce{COOH}$
$ > \ce{C= O}$ and $-\ce{OH}$
$-\ce{OH}$ and $-\ce{CHO}$

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Always six carbon atoms.
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$D-$threose, $D-$erythrose, $L-$threose, $L-$erythrose.
$L-$erythrose, $L-$threose, $D-$erythrose, $D-$threose.
$D-$erythrose, $D-$threose, $L-$erythrose, $L-$threose.

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Assertion and reason both are correct statements and reason is correct explanation for assertion.
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Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.

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Assertion: All amino acids are optically active.

Reason: Amino acids contain asymmetric carbon atoms.

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Reason: An egg contains a soluble globular protein called albumin which is present in the white part.

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Reason: Out of 20 amino acids, only 12 amino acids can be synthesised by human body.

Assertion: The helical structure of protein is stabilised by intramolecular hydrogen bond between -NH and carbonyl oxygen.

Reason: Sanger's reagent is used for the identification of N-tenninal amino acid of peptide chain.

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Assertion and reason both are correct statements and reason is correct explanation for assertion.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.

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Reason: At high concentration, migration ofions is slow.

Assertion: The molar conductance of weak electrolyte at infinite dilution is equal to the sum of molar conductance of cations and anions.

Reason: Kohlrausch's law is applicable for strong electrolytes.

Assertion: Equivalent conductance of all electrolytes increases with increasing concentration.

Reason: More number ofions are available per gram equivalent at higher concentration.

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Reason: On dilution, number of ions per millilitre decreases but total number ofions increases considerably.

Assertion: The ratio of specific conductivity to the observed conductance does not depend upon the concentration of the solution taken in the conductivity cell.

Reason: Specific conductivity decreases with dilution whereas observed conductance increases with dilution.

Read the passage given below and answer the following questions:
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The following questions are multiple choice questions. Choose the most appropriate answer:

A mixture of benzaldehyde and formaldehyde on heating with aqueous $\ce{NaOH}$ solution gives:

Benzyl alcohol and sodium formate.
Sodium benzoate and methyl alcohol.
Sodium benzoate and sodium formate.
Benzyl alcohol and methyl alcohol.

Which of the following compounds will undergo Cannizzaro reaction?

$\ce{CH_3CHO}$
$\ce{CH_3COCH_3}$
$\ce{C_6H_5CHO}$
$\ce{C_6H_5CH_2CHO}$

Trichloroacetaldehyde is subjected to Cannizzaro's reaction by using $\ce{NaOH}$. The mixture of the products contains sodium trichloroacetate ion and another compound. The other compounds is:

$2, 2, 2-$ trichloroethanol.
Trichloromethanol.
$2, 2, 2-$ trichloropropanol.
Chloroform.

In Cannizzaro reaction given below:

$2\text{PhCHO}\xrightarrow{\stackrel{-}{\hbox{ OH}}}\text{PhCH}_2+\text{OH}+\text{PhCO}_2^-$ the slowest step is:

The attack $^-OH$ at the carboxyl group.
The transfer of hydride to the carbonyl group.
The abstraction of proton from the carboxylic group.
The deprotonation of $\ce{PhCH_2OH}.$

Which of the following reaction will not result in the formation of carbon $-$ carbon bonds?

Cannizzaro reaction.
Wurtz reaction.
Reimer $-$Tiemann reaction.
Friedel $-$ Crafts' acylation.