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NTA JEE Main 20th July 2021 Shift 1 - Chemistry

For the following questions answer them individually

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

Given below are two statements : One is labelled as Assertion A and other is labelled as Reason R.
Assertion A : The dihedral angles in H$$_2$$O$$_2$$ 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:

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

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 dispersed phase has a very different refractive index from the dispersion medium. Choose the most appropriate conditions from the options given below:

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

In the given reaction 3-Bromo-2, 2-dimethyl butane $$\xrightarrow{C_2H_5OH}$$ 'A' (Major Product). Product A is:

Compound A is converted to B on reaction with CHCl$$_3$$ and KOH. The compound B is toxic and can be decomposed by C. A, B and C respectively are:

Identify the incorrect statement from the following.

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

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$$2$$ SO$$_2$$(g) + O$$_2$$(g) $$\rightleftharpoons$$ 2 SO$$_3$$(g)
In an equilibrium mixture, the partial pressures are
P$$_{SO_3}$$ = 43 kPa; P$$_{O_2}$$ = 530 Pa and
P$$_{SO_2}$$ = 45 kPa. The equilibrium constant K$$_P$$ = ___ $$\times 10^{-2}$$. (Nearest integer)

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250 mL of 0.5M NaOH was added to 500 mL of 1M HCl. The number of unreacted HCl molecules in the solution is p$$\times 10^{21}$$. Find out p.
(Nearest integer) (N$$_A$$ = 6.022 $$\times 10^{23}$$)

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At 20$$^\circ$$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$$^\circ$$C above an equimolar mixture of benzene and methyl benzene is ___ $$\times 10^{-2}$$. (Nearest integer)

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The inactivation rate of a 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 ___ $$\times 10^{-3}$$ min$$^{-1}$$.
(Nearest integer) [Use : ln 10 = 2.303; $$\log_{10} 3 = 0.477$$ property of logarithm: $$\log x^y = y \log x$$]

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