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Chemistry

Which of the following compound will most easily be attacked by an electrophile?

In case of isoelectronic species the size of \( \text{F}^- \), \( \text{Ne} \) and \( \text{Na}^+ \) is affected by:

Which of the following reactions are disproportionation reactions?
(A) \( \text{Cu}^+ \rightarrow \text{Cu}^{2+} + \text{Cu} \)
(B) \( 3\text{MnO}_4^{2-} + 4\text{H}^+ \rightarrow 2\text{MnO}_4^- + \text{MnO}_2 + 2\text{H}_2\text{O} \)
(C) \( 2\text{KMnO}_4 \rightarrow \text{K}_2\text{MnO}_4 + \text{MnO}_2 + \text{O}_2 \)
(D) \( 2\text{MnO}_4^- + 3\text{Mn}^{2+} + 2\text{H}_2\text{O} \rightarrow 5\text{MnO}_2 + 4\text{H}^+ \)
Choose the correct answer from the options given below:

We have three aqueous solutions of \( \text{NaCl} \) labelled as ‘A’, ‘B’ and ‘C’ with concentration \( 0.1 \, \text{M} \), \( 0.01 \, \text{M} \), \( 0.001 \, \text{M} \), respectively. The value of van’t Hoff factor \( (i) \) for these solutions will be in the order:

Match List-I with List-II.

Choose the correct answer from the options given below:

Ionic reactions with organic compounds proceed through:
(A) homolytic bond cleavage (B) heterolytic bond cleavage (C) free radical formation (D) primary free radical (E) secondary free radical
Choose the correct answer from the options given below:

In acidic medium, \( \mathrm{K_2Cr_2O_7} \) shows oxidising action as represented in the half reaction:
$Cr_2O_7^{2-} + XH^+ + Ye^{\ominus} \rightarrow 2A + ZH_2O$
\( X \), \( Y \), \( Z \) and \( A \) respectively are:

Choose the correct option for free expansion of an ideal gas under adiabatic condition from the following:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Haloalkanes react with \( \mathrm{KCN} \) to form alkyl cyanides as a main product while with \( \mathrm{AgCN} \) form isocyanide as the main product.
Reason (R): \( \mathrm{KCN} \) and \( \mathrm{AgCN} \) both are highly ionic compounds.
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements:
Statement (I) : A solution of \( [\mathrm{Ni}(\mathrm{H_2O})_6]^{2+} \) is green in colour.
Statement (II) : A solution of \( [\mathrm{Ni}(\mathrm{CN})_4]^{2-} \) is colourless.
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements:
Statement (I) : Potassium hydrogen phthalate is primary standard for standardisation of sodium hydroxide solution.
Statement (II) : In this titration phenolphthalein can be used as indicator.
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements:
Statement (I) : The \( \mathrm{NH_2} \) group in aniline is ortho and para directing and powerful activating group.
Statement (II) : Aniline does not undergo Friedel-Craft’s reaction (alkylation and acylation).
In the light of the above statements, choose the most appropriate answer from the options given below:

Which of the following complex is homoleptic?

Given below are two statements:
Statement (I) : Aminobenzene and aniline are same organic compounds.
Statement (II) : Aminobenzene and aniline are different organic compounds.
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : \( \mathrm{PH_3} \) has lower boiling point the \( \mathrm{NH_3} \).
Reason (R) : In liquid state \( \mathrm{NH_3} \) molecules are associated through vander Waal's forces, but \( \mathrm{PH_3} \) molecules are associated through hydrogen bonding.
In the light of the above statements, choose the most appropriate answer from the options given below:

In Kjeldahl's method for estimation of nitrogen, \( \mathrm{CuSO_4} \) acts as:

If one strand of a DNA has the sequence \( \text{ATGCTTCA} \), sequence of the bases in complementary stand is:

Identify A and B in the following sequence of reaction:

Arrange the bonds in order of increasing ionic character in the molecules \( \mathrm{LiF} \), \( \mathrm{K_2O} \), \( \mathrm{N_2} \), \( \mathrm{SO_2} \) and \( \mathrm{ClF_3} \)

According to the wave-particle duality of matter by de-Broglie, which of the following graph plot presents most appropriate relationship between wavelength of electron \( \lambda \) and momentum of electron \( p \)?

The number of molecules/ion/s having trigonal bipyramidal shape is _______.
\( \mathrm{PF_5} \), \( \mathrm{BrF_5} \), \( \mathrm{PCl_5} \), \( [\mathrm{Pt\!Cl_4}]^{2-} \), \( \mathrm{BF_3} \), \( \mathrm{Fe(CO)_5} \)

Number of optical isomers for \( 2 \)-chlorobutane ______.

Consider the following reaction:
\( 3\mathrm{PbCl_2} + 2(\mathrm{NH_4})_3\mathrm{PO_4} \rightarrow \mathrm{Pb_3(PO_4)_2} + 6\mathrm{NH_4Cl} \)
If \( 72 \) mmol of \( \mathrm{PbCl_2} \) is mixed with \( 50 \) mmol of \( (\mathrm{NH_4})_3\mathrm{PO_4} \), then the amount of \( \mathrm{Pb_3(PO_4)_2} \) formed is ______ mmol. (Nearest integer)

Among the following oxides of p-block elements, number of oxides having amphoteric nature is ______.
\( \mathrm{Cl_2O_7} \), \( \mathrm{CO} \), \( \mathrm{PbO_2} \), \( \mathrm{N_2O} \), \( \mathrm{NO} \), \( \mathrm{Al_2O_3} \), \( \mathrm{SiO_2} \), \( \mathrm{N_2O_5} \), \( \mathrm{SnO_2} \)

The potential for the given half cell at \( 298 \, \text{K} \) is (−) _______ \( \times 10^{-2} \, \text{V} \).
\( 2\mathrm{H}^+(\mathrm{aq}) + 2e^- \rightarrow \mathrm{H}_2(\mathrm{g}) \)
\( [\mathrm{H}^+] = 1 \, \text{M}, \; P_{\mathrm{H}_2} = 2 \, \text{atm} \)
[Given : \( 2.303 \, \frac{RT}{F} = 0.06 \, \text{V}, \; \log 2 = 0.3 \)]

The lowest oxidation number of an atom in a compound \( \mathrm{A_2B} \) is \( -2 \). The number of electrons in its valence shell is _______.

The ratio of $\frac{^{14}\text{C}}{^{12}\text{C}}$ in a piece of word is $\frac{1}{8}$ part that of atmosphere. If half life of $^{14}\text{C}$ is 5730 years, the age of wood sample is ______ years.

Total number of deactivating groups in aromatic electrophilic substitution reaction among the following is _______.

The number of white coloured salts, among the following is _______.
(a) \( \mathrm{SrSO_4} \) (b) \( \mathrm{Mg(NH_4)PO_4} \) (c) \( \mathrm{BaCrO_4} \) (d) \( \mathrm{Mn(OH)_2} \)
(e) \( \mathrm{PbSO_4} \) (f) \( \mathrm{PbCrO_4} \) (g) \( \mathrm{AgBr} \) (h) \( \mathrm{PbI_2} \)
(i) \( \mathrm{CaC_2O_4} \) (j) \( [\mathrm{Fe(OH)_2(CH_3COO)}] \)

\( K_a \) for \( \mathrm{CH_3COOH} \) is \( 1.8 \times 10^{-5} \) and \( K_b \) for \( \mathrm{NH_4OH} \) is \( 1.8 \times 10^{-5} \). The \( \mathrm{pH} \) of ammonium acetate solution will be ______.

JEE Main 2024 1st Feb Morning Shift

Mathematics Physics Chemistry

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In Kjeldahl's method for estimation of nitrogen, \( \mathrm{CuSO_4} \) acts as: