List of top Chemistry Questions

How do you explain the following?
(a) Presence of an aldehyde group in glucose.
(b) Presence of five –OH groups in glucose.
Draw the structures of major monohalo products in each of the following reactions:
methylbenzene (CH3C6H5)

\( \text{CH}_3\text{C}_6\text{H}_5 + \text{HI} \longrightarrow \) ?
(b) \( \text{C}_6\text{H}_6 + \text{Br}_2 \longrightarrow \) Heat or UV light ?
Assertion (A): Phenol is strongly acidic as compared to ethanol.
Reason (R): Phenoxide ion is more stable than ethoxide ion.
Pyranose ring of glucose is formed due to the reaction between:
Assertion (A): Hydrolysis of an ester follows first order kinetics.
Reason (R): The concentration of water does not get altered much during the reaction.
Assertion (A): Actinoids show wide range of oxidation states.
Reason (R): Actinoids are radioactive in nature.
The unit of rate and rate constant are the same for a:
Assertion (A): Boiling point of (CH₃)₃N is higher than that of CH₃CH₂CH₂NH₂.
Reason (R): Hydrogen bonding is more extensive in CH₃CH₂CH₂NH₂.
Which of the following cell converts the energy of combustion of fuel into electrical energy?
Which of the following complex ions is not optically active?
Which one of the following amines gives an alcohol on reaction with HNO₂?
Which of the following is the softest metal?
The freezing point of one molal KCl solution, assuming KCl to be completely dissociated in water, is: (\(K_f\) for water = 1.86 K kg mol\(^{-1}\))
A solution of acetone in ethanol:
According to Werner’s theory of coordination compounds:
In the Hinsberg method for separation of primary, secondary, and tertiary amines, the reagent used is:
Williamson synthesis of preparing unsymmetrical ether is:
Which of the following compounds would be hydrolyzed by aqueous KOH most easily?
Which of the following compounds will give a positive Iodoform test?
Which of the following is not a colligative property?
According to the generally accepted definition of the ideal solution there are equal interaction forces acting between molecules belonging to the same or different species. (This is equivalent to the statement that the activity of the components equals the concentration.) Strictly speaking, this concept is valid in ecological systems (isotopic mixtures of an element, hydrocarbons mixtures, etc.). It is still usual to talk about ideal solutions as limiting cases in reality since very dilute solutions behave ideally with respect to the solvent. This law is further supported by the fact that Raoult’s law empirically found for describing the behaviour of the solvent in dilute solutions can be deduced thermodynamically via the assumption of ideal behaviour of the solvent.
Ribose and 2-deoxyribose have an important role in biology. Among the most important derivatives are those with phosphate groups attached at the 5 position. Mono-, di- and tri-phosphate forms are important, as well as 3-5 cyclic monophosphates. Purines and pyrimidines form an important class of compounds with ribose and deoxyribose. When these purine and pyrimidine derivatives are coupled to a ribose sugar, they are called nucleosides.
Arrange the following compounds as asked:
(a) In decreasing order of pKb values
C2H5NH2, (C2H5)2NH, C6H5NHCH3, C6H5NH2
(b) In increasing order of boiling point
C2H5OH, C2H5NH2, (CH3)2NH
(c) In increasing order of solubility in water
C6H5NH2, (C2H5)2NH, C2H5NH2

An aromatic compound ‘A’ with molecular formula C8H8O gives positive 2,4-DNP test. It gives yellow precipitate of compound ‘B’ on treatment with sodium hypoiodite. Compound ‘A’ does not react with Tollen’s or Fehling’s reagent; on drastic oxidation with KMnO4 it forms a carboxylic acid ‘C’. Elucidate the structures of A, B, and C. Also give their IUPAC names.

The reaction between A2 (g) and B2 (g) was carried out in a sealed isothermal container. The rate law for the reaction was found to be:

Rate = \( k[\text{A}_2][\text{B}_2] \)

If 1 mole of A2 (g) was added to the reaction chamber and the temperature was kept constant, then predict the change in rate of the reaction and the rate constant.