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The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is:
[Given: The threshold frequency of platinum is \( 1.3 \times 10^{15} \, \mathrm{s}^{-1} \) and \( h = 6.6 \times 10^{-34} \, \text{J s} \).]

At \( 25^{\circ}\mathrm{C} \) and \( 1 \, \text{atm} \) pressure, the enthalpy of combustion of benzene \( (l) \) and acetylene \( (g) \) are \( -3268 \, \mathrm{kJ \, mol^{-1}} \) and \( -1300 \, \mathrm{kJ \, mol^{-1}} \), respectively. The change in enthalpy for the reaction \( 3\mathrm{C_2H_2} \, (g) \rightarrow \mathrm{C_6H_6} \, (l) \).

Solute A associates in water. When \( 0.7 \, \mathrm{g} \) of solute A is dissolved in \( 42.0 \, \mathrm{g} \) of water, it depresses the freezing point by \( 0.2^{\circ}\mathrm{C} \). The percentage association of solute A in water, is:
[Given: Molar mass of A \( = 93 \, \mathrm{g \, mol^{-1}} \). Molal depression constant of water is \( 1.86 \, \mathrm{K \, kg \, mol^{-1}} \).]

The \( K_{sp} \) for bismuth sulphide \( (\mathrm{Bi_2S_3}) \) is \( 1.08 \times 10^{-73} \). The solubility of \( \mathrm{Bi_2S_3} \) in \( \mathrm{mol \, L^{-1}} \) at \( 298 \, \mathrm{K} \) is

Match List I with List II.

Choose the correct answer from the options given below:

The correct order of electron gain enthalpies of \( \mathrm{Cl} \), \( \mathrm{F} \), \( \mathrm{Te} \) and \( \mathrm{Po} \) is

Given below are two statements.
Statement I: During electrolytic refining, blister copper deposits precious metals.
Statement II: In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.
In the light of the above statements, choose the correct answer from the options given below.

Given below are two statements one is labeled as Assertion A and the other is labeled as Reason R:
Assertion A: The amphoteric nature of water is explained by using Lewis acid/base concept.
Reason R: Water acts as an acid with \( \text{\(NH_3\)} \) and as a base with \( \text{\(H_2S\)} \).
In the light of the above statements choose the correct answer from the options given below:

The correct order of reduction potentials of the following pairs is
A. \( {Cl_2 / Cl^-} \)
B. \( {I_2 / I^-} \)
C. \( {Ag^+ / Ag} \)
D. \( {Na^+ / Na} \)
E. \( {Li^+ / Li} \)
Choose the correct answer from the options given below.

The number of bridged oxygen atoms present in compound B formed from the following reaction is

The metal ion (in gaseous state) with lowest spin-only magnetic moment value is

Given below are two statements: one is labeled as Assertion A and the other is labeled as Reason R.
Assertion A: Polluted water may have a value of BOD of the order of \( 17 \) ppm.
Reason R: BOD is measure of oxygen required to oxidise both the biodegradable and non-biodegradable organic material in water.
In the light of the above statements, choose the most appropriate answer from the options given below.

Given below are two statements: one is labeled as Assertion A and the other is labeled as Reason R.
Assertion A: A mixture contains benzoic acid and naphthalene. The pure benzoic acid can be separated out by the use of benzene.
Reason R: Benzoic acid is soluble in hot water.
In the light of the above statements, choose the most appropriate answer from the options given below.

During halogen test, sodium fusion extract is boiled with concentrated \( \mathrm{HNO_3} \) to

Amongst the following, the major product of the given chemical reaction is

In the given reaction

‘A’ can be

Which of the following conditions or reaction sequence will NOT give acetophenone as the major product?

The major product formed in the following reaction, is

Which of the following ketone will NOT give enamine on treatment with secondary amines? [where \( t\text{-}\mathrm{Bu} \) is \( -\mathrm{C(CH_3)_3} \)]

An antiseptic dettol is a mixture of two compounds ‘A’ and ‘B’ where A has \( 6\pi \) electrons and B has \( 2\pi \) electrons. What is ‘B’?

A protein ‘A’ contains \( 0.30\% \) of glycine (molecular weight \( 75 \)). The minimum molar mass of the protein ‘A’ is __________ \( \times 10^3 \, \mathrm{g\, mol^{-1}} \) [nearest integer]

A rigid nitrogen tank stored inside a laboratory has a pressure of \( 30 \, \mathrm{atm} \) at \( 06{:}00 \,\mathrm{am} \) when the temperature is \( 27^{\circ}\mathrm{C} \). At \( 03{:}00 \,\mathrm{pm} \), when the temperature is \( 45^{\circ}\mathrm{C} \), the pressure in the tank will be __________ \( \mathrm{atm} \). [nearest integer]

Amongst \( \mathrm{BeF_2} \), \( \mathrm{BF_3} \), \( \mathrm{H_2O} \), \( \mathrm{NH_3} \), \( \mathrm{CCl_4} \) and \( \mathrm{HCl} \), the number of molecules with non-zero net dipole moment is __________.

At \( 345 \,\mathrm{K} \), the half life for the decomposition of a sample of a gaseous compound initially at \( 55.5 \,\mathrm{kPa} \) was \( 340 \,\mathrm{s} \). When the pressure was \( 27.8 \,\mathrm{kPa} \), the half life was found to be \( 170 \,\mathrm{s} \). The order of the reaction is ____________. [integer answer]

A solution of \( \mathrm{Fe_2(SO_4)_3} \) is electrolyzed for \( x \) \( \text{min} \) with a current of \( 1.5 \, \text{A} \) to deposit \( 0.3482 \, \text{g} \) of \( \mathrm{Fe} \). The value of \( x \) is ___________ [nearest integer]
[Given : \( 1 \, \text{F} = 96500 \, \text{C} \, \text{mol}^{-1} \) ]
Atomic mass of \( \mathrm{Fe} = 56 \, \text{g} \, \text{mol}^{-1} \)

Consider the following reactions :
\( \mathrm{PCl_3} + \mathrm{H_2O} \rightarrow A + \mathrm{HCl} \)
\( A + \mathrm{H_2O} \rightarrow B + \mathrm{HCl} \)
The number of ionisable protons present in the product \( B \) is ______________.

Amongst \( \mathrm{FeCl_3, \; 3H_2O, \; K_3[Fe(CN)_6]} \) and \( [\mathrm{Co(NH_3)_6}]\mathrm{Cl_3} \), the spin-only magnetic moment value of the inner-orbital complex that absorbs light at shortest wavelength is ___________ B.M. [nearest integer]

The Novolac polymer has mass of \( 963 \, \text{g} \). The number of monomer units present in it are ___________.

How many of the given compounds will give a positive Biuret test ___________?
Glycine, Glycylalanine, Tripeptide, Biuret

The neutralization occurs when \( 10 \, \text{mL} \) of \( 0.1 \, \text{M} \) acid ‘\( A \)’ allowed to react with \( 30 \, \text{mL} \) of \( 0.05 \, \text{M} \) base \( \mathrm{M(OH)_2} \). The basicity of the acid ‘\( A \)’ is ______________.
[\( \mathrm{M} \) is a metal]

JEE Main 2022 25th June Evening Shift

Physics Chemistry Mathematics

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How many of the given compounds will give a positive Biuret test ___________?
Glycine, Glycylalanine, Tripeptide, Biuret