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Chemistry

Given below are two statements: One is labeled as Assertion A and the other is labelled as Reason R.
Assertion A: The dihedral angles in \( \mathrm{H_2O_2} \) in gaseous phase is \( 90.2^\circ \) and in solid phase is \( 111.5^\circ \).
Reason 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 A and R.

For above chemical reactions, identify the correct statement from the following.

Which among the above compound/s does /do not form Silver mirror when treated with Tollen’s reagent?

The set in which compounds have different nature is:

The metal that can be purified economically by fractional distillation method is:

Given below are two statements. One is labeled as Assertion A and the other is labelled as Reason R.
Assertion A: Sharp glass edge becomes smooth on heating it upto its melting point.
Reason R: The viscosity of glass decrease on melting.
Choose the most appropriate answer from the options given below.

Green Chemistry in day-to-day life is in the use of ;

Chemical nature of the nitrogen oxide compound obtained from a reaction of concentrated nitric acid and \( \mathrm{P_4O_{10}} \) (in \( 4:1 \) ratio) is:

In the given reaction \( \displaystyle 3\text{-Bromo-2,2-dimethylbutane} \xrightarrow{\text{C}_2\text{H}_5\text{OH}} \underset{(\text{Major Product})}{\text{'A'}} \) is:
Product \(A\) is:

The species given below that does NOT show disproportionation reaction is:

Orlon fibres are made up of:

Compound \( A \) is converted to \( B \) on reaction with \( \mathrm{CHCl_3} \) and \( \mathrm{KOH} \). The compound \( B \) is toxic and can be decomposed by \( C \). \( A \), \( B \) and \( C \) respectively are:

Among the given species the Resonance stabilized carbocations are:

The correct order of intensity of colors of the compounds is:

A s-block element \( \text{(M)} \) reacts with oxygen to form an oxide of the formula \( \text{MO}_2 \). The oxide is pale yellow in colour and paramagnetic. The element \( \text{(M)} \) is:

Identify the incorrect statement from the following:

According to the valence bond theory the hybridization of central metal atom is \( dsp^2 \) for which one of the following compounds?

An inorganic Compound ‘X’ on treatment with concentrated \( \text{H}_2\text{SO}_4 \) produces brown fumes and gives dark brown ring with \( \text{FeSO}_4 \) in presence of concentrated \( \text{H}_2\text{SO}_4 \). Also Compound ‘X’ gives precipitate ‘Y’, when its solution in dilute \( \text{HCl} \) is treated with \( \text{H}_2\text{S} \) gas. The precipitate ‘Y’ on treatment with concentrated \( \text{HNO}_3 \) followed by excess of \( \text{NH}_4\text{OH} \) further gives deep blue coloured solution, Compound ‘X’ is:

The correct structure of Rhumann’s Purple, the compound formed in the reaction of ninhydrin with proteins is:

The conditions given below are in the context of observing Tyndall effect in colloidal solutions:
(A) The diameter of the colloidal particles is comparable to the wavelength of light used.
(B) The diameter of the colloidal particles is much smaller than the wavelength of light used
(C) The diameter of the colloidal particles is much larger than the wavelength of light used.
(D) The refractive indices of the dispersed phase and the dispersion medium are comparable.
(E) The disperse phase has a very different refractive index from the dispersion medium.
Choose the most appropriate conditions from the options given below.

The number of nitrogen atoms in a semicarbazone molecule of acetone is ______

An average person needs about \( 10000 \, \text{kJ} \) energy per day. The amount of glucose (molar mass \( = 180.0 \, \text{g mol}^{-1} \)) needed to meet this energy requirement is __________ \( \text{g} \). (Nearest integer)
(Use : \( \Delta_c H (\text{glucose}) = -2700 \, \text{kJ mol}^{-1} \).)

At \( 20^\circ \text{C} \), the vapour pressure of benzene is \( 70 \) torr and that of methyl benzene is \( 20 \) torr. The mole fraction of benzene in the vapor phase at \( 20^\circ \text{C} \) above an equimolar mixture of benzene and methyl benzene is _____ \( \times 10^{-2} \). (Nearest integer)

The Azimuthal quantum number for the valence electrons of \( \mathrm{Ga^+} \) ion is ______.
(Atomic number of \( \mathrm{Ga} = 31 \))

To synthesis \( 1.0 \, \text{mole} \) of 2-methylpropan-2-ol from Ethylethanoate ________ equivalents of \( \mathrm{CH_3MgBr} \) reagent will be required. (Integer value)

\( 250 \, \text{mL} \) of \( 0.5 \, \text{M} \) \( \mathrm{NaOH} \) was added to \( 500 \, \text{mL} \) of \( 1 \, \text{M} \) \( \mathrm{HCl} \). The number of unreacted \( \mathrm{HCl} \) molecules in the solution after complete reaction is ______ \( \times 10^{21} \). (Nearest integer). ( \( N_A = 6.022 \times 10^{23} \) ).

The inactivation rate of viral preparation is proportional to the amount of virus. In the first minute after preparation, \( 10\% \) of the virus is inactivated. The rate constant for viral inactivation is ______ \( \times 10^{-3} \, \text{min}^{-1} \). (Nearest integer). [Use: \( \ln 10 = 2.303 \); \( \log_{10} 3 = 0.477 \); property of logarithm: \( \log x^{y} = y \log x \) ]

\( 2\mathrm{SO_2}(g) + \mathrm{O_2}(g) \rightleftharpoons 2\mathrm{SO_3}(g) \)
In an equilibrium mixture, the partial pressures are \( P_{\mathrm{SO_3}} = 43 \, \text{kPa} \) ; \( P_{\mathrm{O_2}} = 530 \, \text{Pa} \) and \( P_{\mathrm{SO_2}} = 45 \, \text{kPa} \). The equilibrium constant \( K_p = \) ______ \( \times 10^{-2} \). (Nearest integer)

The spin-only magnetic moment value for the complex \( [\mathrm{Co(CN)_6}]^{4-} \) is ________ BM. [At. no. of Co \( = 27 \)]

The number of lone pair of electrons on the central I atom in \( \mathrm{I_3^-} \) is ________.

JEE Main 2021 20th July Morning Shift

Physics Chemistry Mathematics

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Compound \( A \) is converted to \( B \) on reaction with \( \mathrm{CHCl_3} \) and \( \mathrm{KOH} \). The compound \( B \) is toxic and can be decomposed by \( C \). \( A \), \( B \) and \( C \) respectively are: