List of top Chemistry Questions asked in GATE CY

The given zirconocene compound, (η⁵-Cp)₂ZrEt₂, when heated in the presence of an equimolar amount of PMe₃ results in the formation of a compound X which obeys the 18-electron rule. The reaction also resulted in the release of a saturated hydrocarbon.

[Given: Atomic number of Zr = 40]

The structure of compound X is:

The homogeneous catalyst whose metal ion does NOT undergo either oxidation or reduction in any of the steps during the hydrogenation of terminal olefins is:

The reaction that proceeds through an oxidative addition followed by a reductive elimination is:

[Given: Atomic numbers Ni = 28, Ta = 73, Zr = 40, Pt = 78]

The expressions for the vapour pressure of solid (\( p_1 \)) and vapour pressure of liquid (\( p_2 \)) phases of a pure substance, respectively, are \[ \ln p_1 = \frac{-2000}{T} + 5 \quad {and} \quad \ln p_2 = \frac{-4000}{T} + 10 \] The triple point temperature of this substance is ________ K (in integer).}

The ratio of the fundamental vibrational frequencies \( \left( \nu_{^{13}C^{16}O} / \nu_{^{12}C^{16}O} \right) \) of two diatomic molecules \( ^{13}C^{16}O \) and \( ^{12}C^{16}O \), considering their force constants to be the same, is ___________ (rounded off to two decimal places).}

The specific rotation of enantiomerically pure (S)-2-butanol is \( +14^\circ \). The specific rotation of the enantiomeric mixture of 2-butanol obtained from an asymmetric reduction of 2-butanone is found to be \( +7^\circ \).

The percentage of (R)-2-butanol present in the reaction mixture is _________ (in integer).

Partial hydrolysis of a pentapeptide yields all possible tripeptides and dipeptides. The dipeptides that are obtained upon hydrolysis are given below:

Val–Ala
Gln–His
Phe–Val
Ala–Gln

The total number of tripeptides obtained that contain ‘Ala’ as one of the amino acids is 2 (in integer).

The total number of hyperfine lines expected in the EPR spectrum of •CH₂OH (radical) is ___________ (in integer).

Xe and F₂ in 1:1 molar ratio when mixed in a closed flask and kept in sunlight for a day, gave white crystals of a compound Q. Two equivalents of Q on reaction with one equivalent of AsF₅ gave an ionic compound X⁺Y^– with the cation having two Xe atoms. The total number of lone pairs present on the cation X⁺ is ___________ (in integer).

The thermodynamic criterion/criteria for a spontaneous process is/are

Consider two non-interacting particles confined to a one-dimensional box with infinite potential barriers. Their wavefunctions are \( \psi_1 \) and \( \psi_2 \), and energies are \( E_1 \) and \( E_2 \), respectively. The INCORRECT statement(s) about this system is/are:

Choose the correct option(s) with regard to mechanism of the following transformation.

Among the given options, the possible product(s) that can be obtained from the following reaction is/are:

The correct option(s) of reagents and reaction sequences suitable for carrying out the following transformation is/are:

Compound(s) that show(s) an intense peak at \( m/z = 120 \) in the EI mass spectrum is/are:

The essential symmetry(ies) for a monoclinic crystal system is/are the presence of:

Under the conditions mentioned for each reaction, the reaction(s) that would give borazine (B₃N₃H₆) as the major product is/are:

The Vaska’s complex trans-IrCl(CO)(PPh₃)₂ shows a band at 1967 cm⁻¹ for the \( \nu_{\text{CO}} \) stretching vibration in its infrared spectrum. The complex(es) that will show an increase in the \( \nu_{\text{CO}} \) stretching vibration from 1967 cm⁻¹ is/are:

The translational, vibrational, and rotational molecular partition functions for a system containing ideal diatomic gas molecules in the canonical ensemble (N, V, T) are written as \( q_{{trans}}, q_{{vib}}, \) and \( q_{{rot}} \), respectively. The option that correctly defines their thermodynamic variable(s) dependency is:

The symmetry element that does NOT belong to the \( C_{4v} \) point group is:

A disaccharide X does NOT show mutarotation in aqueous solution. Acidic hydrolysis of X affords two different monosaccharides. The disaccharide X is:

In the ¹H-NMR spectrum of the following molecule, the signal of proton H_a appears as:

For an unambiguous single step synthesis of the following target molecule (TM), the best bond disconnection in its retrosynthetic analysis is:

An aqueous solution of Co(ClO₄)₂·6H₂O is light pink in colour. Addition of conc. HCl results in an intense blue coloured solution due to the formation of a new species. The new species among the following is:

[Given: Atomic number of Co = 27]

Upon cooling from room temperature, the magnetic susceptibility of MnO slowly increases until 118 K, and then it decreases. This phenomenon is known as: