List of top Chemistry Questions

What is present in a racemic mixture?
An unknown element 'E' forms two compounds: \(EO_{2}\) and \(EX_{4}\). To which group does element 'E' belong?
What is the structure of Cyclohexyl methanol?
Match the Column-I (Ligands) with Column-II (Ligand type):
Column-I: (I) \(NO_{2}^{-}\), (II) \(OH^{-}\), (III) \(C_{2}O_{4}^{2-}\), (IV) EDTA.
Column-II: (A) Hexadentate, (B) Bidentate, (C) Monodentate, (D) Ambidentate.
Which colligative property is most suitable for determining molar mass?
What is the hybridisation of carbon atoms in \(CH_{2}=CH-CN\) (Acrylonitrile)?
Why do aryl halides not show nucleophilic substitution reaction?
What is the oxidation state of oxygen in \(O_{2}F_{2}\) and \(O_{3}\)?
What is the magnetic dipole moment of \(Mn^{2+}\;(3d^{5})\)?
Assertion (A): The first ionization enthalpy of nitrogen is higher than that of oxygen.
Reason (R): Nitrogen has a half-filled \(2p\) orbital, which is extra stable.
Which compound undergoes the \(S_{N}2\) reaction the fastest?
What is formed when benzene diazonium chloride (BDC) reacts with phenol?
\(R-CONH_{2}+Br_{2}+4NaOH \rightarrow R-NH_{2}+Na_{2}CO_{3}+2NaBr+2H_{2}O\); this reaction is:
What will be formed when \(CH_{3}-CH=CH_{2}+HBr\) reacts in the presence of peroxide?
The entropy change when 400 J of heat is absorbed reversibly at 400 K is:
100 mL of 2 M HCl is diluted to 500 mL. The molarity of the diluted solution is:
The IUPAC name of CH$_3$CH(OH)CH$_2$CH$_3$ is:
The coordination number of cobalt in [Co(NH$_3$)$_6$]Cl$_3$ is:
According to Molecular Orbital Theory, the bond order of O$_2$ is:
A solution is prepared by dissolving 5.85 g of NaCl (Molar mass = 58.5 g mol$^{-1}$) in water to make 500 mL of solution. The molarity of the solution is:
At equilibrium for the reaction N$_2$(g) + 3H$_2$(g) $\rightleftharpoons$ 2NH$_3$(g), the concentrations are [N$_2$] = 0.20 M, [H$_2$] = 0.60 M and [NH$_3$] = 0.80 M. The value of K$_c$ is:
According to Valence Bond Theory, the hybridization of the central metal ion in [Ni(CN)$_4$]$^{2-}$ is:
Answer the following: (I) Which isomer of C$_4$H$_9$Br is most reactive towards S$_N$1 reaction? (II) Predict the alkene that would be formed by dehydrohalogenation of 1-Bromo-1-methylcyclohexane. (III) Although chlorine shows strong $-I$ effect, yet it is ortho/para-directing in electrophilic aromatic substitution reactions. Why? (ii) Write the major product in the following reactions: (I)
(II)
(I) Which of the following is more reactive towards S$_N$1 reaction: 2-Bromo-2-methylbutane or 1-Bromopentane (II) What type of halide is present in the following compound: \[ \begin{array}{c} CH_3-CH-C=CH_2\\ |\\ CH_3 \end{array} \] \[ | \] \[ Cl \] (III) Why is chloroform stored in dark coloured bottles? (ii) Define the following terms: (I) Ambident Nucleophiles (II) Racemic mixture
What is meant by lanthanoid contraction? (ii) Why do transition metals form coloured compounds? (iii) Why are $E^\circ_{M^{2+}/M}$ values for Mn and Zn more negative than expected? (iv) Which is the most stable oxidation state of Cu and why? (v) Why is Ce$^{4+}$ in aqueous solution a good oxidising agent?