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Chemistry

Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is __________. B, C, N, S, O, F, P, Al, Si

The Molarity \( (M) \) of an aqueous solution containing \( 5.85 \, \mathrm{g} \) of \( \mathrm{NaCl} \) in \( 500 \, \mathrm{mL} \) water is:
(Given: Molar Mass Na : \( 23 \) and Cl : \( 35.5 \, \mathrm{g \, mol^{-1}} \) )

Which of the following nitrogen containing compound does not give Lassaigne’s test?

Match List I with List II:

Choose the correct answer from the options given below:

Which among the following is incorrect statement?

The correct sequence of ligands in the order of decreasing field strength is:

Which of the following is the correct structure of L-Glucose?

Given below are two statements:
Statements I: Acidity of \( \alpha \)-hydrogens of aldehydes and ketones is responsible for Aldol reaction.
Statements II: Reaction between benzaldehyde and ethanol will NOT give Cross-Aldol product.
In the light of the above statements, choose the most appropriate answer from the options given below:

What pressure \( \text{(bar)} \) of \( \mathrm{H_2} \) would be required to make emf of hydrogen electrode zero in pure water at \( 25^\circ \mathrm{C} \)?

Number of complexes from the following with even number of unpaired “\( d \)” electrons is ______.
\( [\mathrm{V}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Cr}(\mathrm{H_2O})_6]^{2+};\ [\mathrm{Fe}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Ni}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Cu}(\mathrm{H_2O})_6]^{2+} \)
[Given atomic numbers : \( \mathrm{V}=23 \), \( \mathrm{Cr}=24 \), \( \mathrm{Fe}=26 \), \( \mathrm{Ni}=28 \), \( \mathrm{Cu}=29 \)]

Which one of the following molecules has maximum dipole moment?

Identify the product in the following reaction:

.

In the precipitation of the iron group \( (\text{III}) \) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to:

The correct order of first ionization enthalpy values of the following elements is:
\( (A) \) \( \mathrm{O} \)
\( (B) \) \( \mathrm{N} \)
\( (C) \) \( \mathrm{Be} \)
\( (D) \) \( \mathrm{F} \)
\( (E) \) \( \mathrm{B} \)
Choose the correct answer from the options given below:

What will be the decreasing order of basic strength of the following conjugate bases ?

$\text{ }^{-}\text{OH}, \text{R}\bar{\text{O}}, \text{CH}_3\text{CO}\bar{\text{O}}, \text{C}\bar{\text{l}}$

The element which shows only one oxidation state other than its elemental form is:

Identify the correct set of reagents or reaction conditions ‘\( X \)’ and ‘\( Y \)’ in the following set of transformation.

One of the commonly used electrode is calomel electrode. Under which of the following categories, calomel electrode comes?

Number of molecules/ions from the following in which the central atom is involved in \( \mathrm{sp}^3 \) hybridization is \( \_\_\_\_\_\_ \).\( \mathrm{NO}_3^- , \ \mathrm{BCl}_3 , \ \mathrm{ClO}_2^- , \ \mathrm{ClO}_3 \)

The number of different chain isomers for \( \mathrm{C}_7\mathrm{H}_{16} \) is \( \_\_\_\_\_\_ \).

\( X \) \( \mathrm{g} \) of ethylamine is subjected to reaction with \( \mathrm{NaNO}_2 / \mathrm{HCl} \) followed by water; evolved dinitrogen gas which occupied \( 2.24 \, \mathrm{L} \) volume at STP. \( X \) is \( \_\_\_\_\_\_ \times 10^{-1} \, \mathrm{g} \).

The de-Broglie’s wavelength of an electron in the \( 4^{\text{th}} \) orbit is \( \_\_\_\_\_\_ \, \pi a_0 \). \( (a_0 = \) Bohr’s radius\() \)

Only \( 2 \, \mathrm{mL} \) of \( \mathrm{KMnO}_4 \) solution of unknown molarity is required to reach the end point of a titration of \( 20 \, \mathrm{mL} \) of oxalic acid \( (2 \, \mathrm{M}) \) in acidic medium. The molarity of \( \mathrm{KMnO}_4 \) solution should be \( \_\_\_\_\_\_ \, \mathrm{M} \).

Consider the following transformation involving first order elementary reaction in each step at constant temperature as shown below.

Some details of the above reactions are listed below.

If the overall rate constant of the above transformation (\( k \)) is given as \( k = \dfrac{k_1 k_2}{k_3} \) and the overall activation energy (\( E_a \)) is \( 400 \, \text{kJ mol}^{-1} \), then the value of \( E_{a3} \) is ______ \( \text{kJ mol}^{-1} \) (nearest integer)

Consider the following reaction \( \mathrm{MnO_2} + \mathrm{KOH} + \mathrm{O_2} \rightarrow A + \mathrm{H_2O} \). Product ‘A’ in neutral or acidic medium disproportionate to give products ‘B’ and ‘C’ along with water. The sum of spin-only magnetic moment values of B and C is ______ \( \text{BM} \). (nearest integer) (Given atomic number of Mn is \( 25 \))

The number of the correct reaction(s) among the following is _______.

The enthalpy of formation of ethane (\( \mathrm{C_2H_6} \)) from ethylene by addition of hydrogen where the bond-energies of \( \mathrm{C{-}H} \), \( \mathrm{C{-}C} \), \( \mathrm{C{=}C} \), \( \mathrm{H{-}H} \) are \( 414 \, \text{kJ} \), \( 347 \, \text{kJ} \), \( 615 \, \text{kJ} \) and \( 435 \, \text{kJ} \) respectively is - ______ \( \text{kJ} \).

Number of molecules/species from the following having one unpaired electron is _______. \( \mathrm{O_2} \), \( \mathrm{O_2^{-1}} \), \( \mathrm{NO} \), \( \mathrm{CN^{-1}} \), \( \mathrm{O_2^{2-}} \)

\( 2.5 \, \text{g} \) of a non-volatile, non-electrolyte is dissolved in \( 100 \, \text{g} \) of water at \( 25^\circ \text{C} \). The solution showed a boiling point elevation by \( 2^\circ \text{C} \). Assuming the solute concentration is negligible with respect to the solvent concentration, the vapor pressure of the resulting aqueous solution is ______ \( \text{mm of Hg} \) (nearest integer)
[Given: Molal boiling point elevation constant of water (\( K_b \)) \( = 0.52 \, \text{K} \cdot \text{kg mol}^{-1} \), \( 1 \) atm pressure \( = 760 \) \( \text{mm of Hg} \), molar mass of water \( = 18 \, \text{g mol}^{-1} \) ]

JEE Main 2024 4th April Morning Shift

Mathematics Physics Chemistry

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The element which shows only one oxidation state other than its elemental form is: