List of top Chemistry Questions

The number of species among the following, having bond order of three is ............. \[ \text{N}_2, \text{F}_2, \text{NO}^+, \text{O}_2^-, \text{N}_2^+, \text{CO}, \text{O}_2, \text{O}_2^{2-} \]

Solubility of PbCO\(_3\) in a buffer of pH 5 is \( X \times 10^{-4} \). The value of \( X \) is ..............................

The molar conductivity of a 0.02 M weak acid HA is 3.2 mS m\(^2\) mol\(^{-1}\) at 298 K. The \( pK_a \) of HA is ....................

The first rotational absorption of \(^{12}C^{16}O\) molecule is observed at 3.84 cm\(^{-1}\). If an isotopic substitution is made with \(^{18}O\) in the molecule, the frequency (in cm\(^{-1}\)) of first rotational absorption is ...............

If \( y + x e^y = \sin x + \tan x \), then the value of \( \frac{dy}{dx} \) at \( x = 0 \) is ...................

The resonance frequency of \( ^1H \) nuclei is 300 MHz in an NMR spectrometer. If the spectrometer is operated at 12 T magnetic field, the resonance frequency (in MHz) of the same \( ^1H \) nuclei is ..................

Number of spin allowed transition(s) possible for \( d^2 \) octahedral configuration is .............

The reaction(s) that will yield cyclic product is(are)

The correct statement(s) among the following is(are)

A yellow compound X is produced after the reaction of \( K_2[Ni(CN)_4] \) with excess of \( K/\text{liq. NH}_3 \) at -33°C. The oxidation state of Ni in the compound X is ..........

Correct statement(s) with respect to defects in solids is(are)

The set(s), in which all the compounds yield achiral products upon treatment with CH\(_3\)MgBr followed by hydrolysis with dilute mineral acid, is(are)

In alkaline medium, which of the following metal ion(s) form(s) red precipitate/coloration with dimethylglyoxime?

The correct statement(s) about the octahedral Mn-complex with spin only magnetic moment of approximately 6.0 \( \mu_B \) is(are)

Consider Langmuir adsorption of a gas on a uniform solid surface having N number of surface sites. The free and adsorbed gas molecules are in dynamic equilibrium. If the fractional surface coverage is \( \theta \), the rate of adsorption of the gas is proportional to

According to VSEPR theory, the set(s) of species having trigonal bipyramidal geometry is(are)

For \([Mn(CO)_6]^{+}\) and \([V(CO)_6]^{-}\) complexes, the correct statement(s) is(are)

The substances, A, B and C undergo chemical reactions according to the scheme given below. \[ \text{A} \xrightarrow{k} \text{B} \xrightarrow{2k} \text{C}, \quad \text{A} \xrightarrow{3k} \text{C} \] At time \( t = 0 \), the [A] = 0.11 M. Considering them to be first order reactions, the concentration of B (in M) at equilibrium is

An organic compound P (C\(_8\)H\(_16\)) produces a meso compound upon oxidation with OsO\(_4\)/NMO. The compound P is

A vessel contains 1 mol of gas A and 2 mol of gas B at 2 bar and 25°C. The gas mixture is compressed such that the final pressure becomes 3 bar without any change in temperature. Considering ideal gas behaviour, the change in Gibbs free energy (in kJ) during the compression is closest to

For van der Waals gases, at the critical point, \( \frac{dP}{dV_m} = 0 \) and

The set of asymmetric top molecules is

The correct order of the dipole moment among the following is

In the following transformation, the number of \( \alpha \) and \( \beta \) particles emitted, respectively, are \[ \begin{matrix} ^{223}_{88}Ra & \xrightarrow{\text{}} & ^{207}_{82}Pb \end{matrix} \]

Wilkinson’s catalyst contains