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Chemistry

In the extraction of copper, its sulphide ore is heated in a reverberatory furnace after mixing with silica to:

Which of the following compounds would give the following set of qualitative analysis?
(i) Fehling’s Test : Positive
(ii) \( \mathrm{Na} \) Fusion extract upon treatment with sodium nitroprusside gives a blood red colour but not Prussian blue.

Caprolactam when heated at high temperature in presence of water, gives:

Amongst the following compounds, which one is an antacid?

Given below are two statements : one is labelled as Assertion (A) and the other labelled as Reason (R).
Assertion (A) : Ketoses gives Seliwanoff’s test faster than Alsoses.
Reason (R) : Ketoses undergoes \( \beta \) - elimination followed by formation of furfural.
In the light of the above statements, choose the correct from the options given below:

The alkaline earth metal sulphate(s) which are readily soluble in water is/are:
A. \( \mathrm{BeSO}_4 \) B. \( \mathrm{MgSO}_4 \) C. \( \mathrm{CaSO}_4 \) D. \( \mathrm{SrSO}_4 \) E. \( \mathrm{BaSO}_4 \)
Choose the correct answer from the options given below:

Match List-I with List-II.

Choose the correct answer from the options given below:

The major products ‘A’ and ‘B’, respectively, are:

Which of the following is correct order of ligand field strength?

Match List-I with List-II.

Choose the correct answer from the options given below:

Formation of photochemical smog involves the following reaction in which A, B and C are respectively.
\( (i)\; \mathrm{NO_2} \xrightarrow{h\nu} A + B \)
\( (ii)\; B + \mathrm{O_2} \longrightarrow C \)
\( (iii)\; A + C \longrightarrow \mathrm{NO_2} + \mathrm{O_2} \)
Choose the correct answer from the options given below:

Given below are two statements: one is labelled as Assertion (A) and the other labelled as Reason (R).
Assertion (A): In expensive scientific instruments, silica gel is kept in watch-glasses or in semipermeable membrane bags.
Reason (R): Silica gel adsorbs moisture from air via adsorption, thus protects the instrument from water corrosion (rusting) and / or prevents malfunctioning
In the light of the above statements, choose the correct from the options given below:

Benzyl isocyanide can be obtained by:

Choose the correct answer from the options given below:

Lithium aluminium hydride can be prepared from the reaction of:

What is the correct order of acidity of the protons marked A – D in the given compounds?

During the qualitative analysis of \( \mathrm{SO_3^{2-}} \) using dilute \( \mathrm{H_2SO_4} \), \( \mathrm{SO_2} \) gas is evolved which turns \( \mathrm{K_2Cr_2O_7} \) solution (acidified with dilute \( \mathrm{H_2SO_4} \)).

For \( \mathrm{OF_2} \) molecule consider the following:
A. Number of lone pairs on oxygen is \( 2 \).
B. FOF angle is less than \( 104.5^\circ \).
C. Oxidation state of O is \( -2 \).
D. Molecule is bent ‘V’ shaped.
E. Molecular geometry is linear.
Correct option are:

In the wet tests for identification of various cations by precipitate, which transition element cation doesn’t belong to group IV in qualitative inorganic analysis?

To inhibit the growth of tumours, identify the compounds used from the following:
A. EDTA B. Coordination compounds of \( \mathrm{Pt} \)
C. D-Penicillamine D. Cis-Platin
Choose the correct answer from the options given below:

Match List-I with List-II.

Choose the correct answer from the options given below

\( 600 \, \text{mL} \) of \( 0.01 \, \text{M} \) \( \mathrm{HCl} \) is mixing with \( 400 \, \text{mL} \) of \( 0.01 \, \text{M} \) \( \mathrm{H_2SO_4} \). The pH of the mixture is ______ \( \times 10^{-2} \). (Nearest integer) [Given : \( \log 2 = 0.30 \), \( \log 3 = 0.48 \), \( \log 5 = 0.69 \), \( \log 7 = 0.84 \), \( \log 11 \, = 1.04 \) ]

The number of electrons involved in the reduction permanganate to manganese dioxide in acidic medium is _______.

If compound A reacts with B following first order kinetics with rate constant \( 2.011 \times 10^{-3} \, \mathrm{s^{-1}} \). The time taken by A (in seconds) to reduce from \( 7 \, \mathrm{g} \) to \( 2 \, \mathrm{g} \) will be _______. (Nearest integer) [\( \log 5 = 0.698 \), \( \log 7 = 0.845 \), \( \log 2 = 0.301 \)]

When \( 2 \, \text{litre} \) of ideal gas expands isothermally into vacuum to a total volume of \( 6 \, \text{litre} \), the change in internal energy is ________ \( \text{J} \). (Nearest integer)

A \( 300 \, \text{mL} \) bottle of soft drink has \( 0.2 \, \text{M} \) \( \mathrm{CO_2} \) dissolved in it. Assuming \( \mathrm{CO_2} \) behaves as an ideal gas, the volume of the dissolved \( \mathrm{CO_2} \) at STP is ________ \( \text{mL} \). (Nearest integer)
[Given : At STP, molar volume of an ideal gas is \( 22.7 \, \text{L mol}^{-1} \)]

A solution containing \( 2 \, \text{g} \) of a non-volatile solute in \( 20 \, \text{g} \) of water boils at \( 373.52 \, \text{K} \). The molecular mass of the solute is ________ \( \text{g mol}^{-1} \). (Nearest integer)
[Given, water boils at \( 373 \, \text{K} \), \( K_b \) for water \( = 0.52 \, \text{K kg mol}^{-1} \)]

Some amount of dichloromethane \( (\mathrm{CH_2Cl_2}) \) is added to \( 671.141 \, \text{mL} \) of chloroform \( (\mathrm{CHCl_3}) \) to prepare \( 2.6 \times 10^{-3} \, \text{M} \) solution of \( \mathrm{CH_2Cl_2} \) (DCM). The concentration of DCM is ________ ppm (by mass). [Given : Atomic mass : \( \mathrm{C} = 12 \), \( \mathrm{H} = 1 \), \( \mathrm{Cl} = 35.5 \) density of \( \mathrm{CHCl_3} = 1.49 \, \text{g cm}^{-3} \)]

The energy of one mole of photons of radiation of frequency \( 2 \times 10^{12} \, \text{Hz} \) in \( \text{J mol}^{-1} \) is ________. (Nearest integer) [Given : \( h = 6.626 \times 10^{-34} \, \text{Js} \), \( N_A = 6.022 \times 10^{23} \, \text{mol}^{-1} \)]

A trisubstituted compound ‘A’, \( \mathrm{C_{10}H_{12}O_2} \) gives neutral \( \mathrm{FeCl_3} \) test positive. Treatment of compound ‘A’ with \( \mathrm{NaOH} \) and \( \mathrm{CH_3Br} \) gives \( \mathrm{C_{11}H_{14}O_2} \), with hydroiodic acid gives methyl iodide and with hot conc. \( \mathrm{NaOH} \) gives a compound B, \( \mathrm{C_{10}H_{12}O_2} \). Compound ‘A’ also decolorizes alkaline \( \mathrm{KMnO_4} \). The number of \( \pi \) bond(s) present in the compound ‘A’ is ________.

Consider the cell $\text{Pt(s)} \mid \text{H}_2(\text{g, 1atm}) \mid \text{H}^+(\text{aq, 1M}) \parallel \text{Fe}^{3+}(\text{aq}), \text{Fe}^{2+}(\text{aq}) \mid \text{Pt(s)}$.

When the potential of the cell is $0.712\text{ V}$ at $298\text{ K}$, the ratio $[\text{Fe}^{2+}]/[\text{Fe}^{3+}]$ is _______.

(Nearest integer) $\left[\text{Given : } \text{Fe}^{3+} + \text{e}^- \rightleftharpoons \text{Fe}^{2+}, E^{\theta}{\text{Fe}^{3+}, \text{Fe}^{2+} \mid \text{Pt}} = 0.771; \frac{2.303RT}{F} = 0.06\text{ V}\right]$

JEE Main 2023 30th Jan Morning Shift

Physics Chemistry Mathematics

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In the extraction of copper, its sulphide ore is heated in a reverberatory furnace after mixing with silica to: