

<
The strength of an acid is determined by the stability of its conjugate base.
Electron-withdrawing groups (-I and -M effects) stabilize the conjugate base by delocalizing the negative charge after the loss of \( \text{H}^+ \). Electron-donating groups (+I and +M effects) destabilize the conjugate base.
In the given options, all are substituted phenols. The substituents are:
Since the nitro group (\( \text{-NO}_2 \)) has the strongest electron-withdrawing effect (-I and -M), it stabilizes the conjugate base of the phenol most effectively. Therefore, the compound with the \( \text{-NO}_2 \) substituent (option 4) is the strongest acid among the given options.

The acid strength of a phenolic compound depends on the electron-withdrawing or electron-donating groups attached to the benzene ring. The electron-withdrawing group increases the acidity of the compound. Among the options, the nitro group (-NO\(_2\)) is a strong electron-withdrawing group through the inductive effect (-I), making the compound with -NO\(_2\) attached to the ring the most acidic.
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
Given below are some nitrogen containing compounds:
Each of them is treated with HCl separately. 1.0 g of the most basic compound will consume ...... mg of HCl.
(Given Molar mass in g mol\(^{-1}\): C = 12, H = 1, O = 16, Cl = 35.5.)

Given below are some nitrogen containing compounds:
Each of them is treated with HCl separately. 1.0 g of the most basic compound will consume ...... mg of HCl.
(Given Molar mass in g mol\(^{-1}\): C = 12, H = 1, O = 16, Cl = 35.5.)

Which of the following slows down the process of setting of the cement?
Incorrect statement for the use of indicators in acid-base titration is :
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,