List of top Chemistry Questions

What is the energy (in J atom\(^{-1}\)) required for the following process?} \[ Li^{2+}(g) \rightarrow Li^{3+}(g) + e^{-} \] (Take the ionization energy for the H atom in the ground state as \(2.18 \times 10^{-18}\) J atom\(^{-1}\)).

Match List - I with List - II.

Choose the correct answer from the options given below :

In IUPAC names the correct order of decreasing priority of functional groups is:

A non-volatile, non-electrolyte solid solute when dissolved in 40 g of a solvent, the vapour pressure of the solvent decreased from 760 mm Hg to 750 mm Hg. If the same solution boils at 320 K, then the number of moles of the solvent present in the solution is ______. (Nearest integer)
[Given: boiling point of the pure solvent = 319.5 K, K_b of the solvent = 0.3 K kg mol⁻¹]

The pH of a solution obtained by mixing 5 mL of 0.1 M $NH_4OH$ solution with 250 mL of 0.1 M $NH_4Cl$ solution is ______ × 10⁻². (Nearest integer)
Given: $pK_b (NH_4OH)$ = 4.74

2.0 g of a bromo hydrocarbon (X) was subjected to Carius analysis, gave 3.36 g of AgBr. The percentage of carbon in the compound (X) is 26.7%. Total number of carbon atoms in the empirical formula for compound (X) is ______.

Consider the following sequence of reactions to give the major product (X). P g of the major product (X) formed is reacted with NaHCO₃ solution to liberate a gas which occupied 11.2 dm³ at STP. P = ______ g.

According to Lewis theory, the total number of σ bond-pairs and lone pair of electrons around the central atom of \(XeO_6^{4-}\) ion is ______.

Identify the colour of compound 'X' in the sequence of the reaction [assuming the Lassaigne's test for Nitrogen/Sulfur or Nitroprusside test].

Match the LIST-I with LIST-II

Product C of the following reaction sequence will be [assuming sequence: Aniline $\xrightarrow{Br_2/H_2O}$ A $\xrightarrow{NaNO_2/HCl}$ B $\xrightarrow{H_3PO_2}$ C]

Amongst the following, the total number of compounds soluble in aqueous NaOH at room temperature is:

Match the LIST-I with LIST-II

An alkene (X) on ozonolysis followed by reduction gives following products. [Assuming products are Glyoxal and Formaldehyde/Acetone based on standard paper context]. The alkene (X) is:

Increasing order of electron withdrawing power of following functional groups is:
a. -CN
b. -COOH
c. -NO₂
d. -I

Match the LIST-I with LIST-II

Correct statements from the following are:
A. Potassium dichromate is an oxidising agent and it oxidises FeSO₄ to Fe₂(SO₄)₃ in acidic medium.
B. Sodium dichromate can be used as primary standard in volumetric estimation.
C. CrO₄²⁻ and Cr₂O₇²⁻ are interconvertible in aqueous solution by varying the pH of the solution.
D. Cr-O-Cr bond angle in Cr₂O₇²⁻ is 126°.
Choose the correct answer:

If the half life of a first order reaction is \(6.93 \text{ minutes}\) then the time required for completion of \(99 %\) of the reaction will be ____ minutes.
(Given : \(\log 2 = 0.3010\))}

The values of pressure equilibrium constant recorded at different temperatures for the following equilibrium reaction have been given below:
\(A(g) \rightleftharpoons B(g) + C(g)\)}

The magnitude of \(\frac{\Delta H^\circ}{R}\) calculated from the above data is ____. (Nearest integer)}

One mole of phenol is treated with dilute \(HNO_3\) at \(298 \text{ K}\) to give a mixture of products. The mixture is separated by steam distillation. The steam volatile compound (X) is separated. The increase in percentage of oxygen in (X) with respect to phenol is ____ \(\times 10^{-1}\) %.
(Given molar mass in \(\text{g mol}^{-1}\) H:1, C:12, N:14, O:16)}

In an estimation of sulphur by Carius method \(0.2 \text{ g}\) of the substance gave \(0.6 \text{ g}\) of \(BaSO_4\). The percentage of sulphur in the substance is ____ %.
(Given molar mass in \(\text{g mol}^{-1}\) S : 32, \(BaSO_4 : 231\))}

Consider the following species:
\(BrF_5, XeF_5^-, BF_4^-, ICl_4^-, XeF_4, SF_4, NH_4^+, ClF_3, XeF_2, ICl_2^-\)
Number of species having \(sp^3d\) hybridized central atom is ____.

Given below are two statements:
Statement I: Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis.
Statement II: Phenolphthalein is a weak base, therefore it dissociates in acidic medium.

Identify the correct statements.
A. Glucose exists in two anomeric forms.
B. Anomers of glucose differ in configuration at C-1 in cyclic hemiacetal structure.
C. Melting point of \(\alpha\)-anomer of glucose is greater than \(\beta\)-anomer.
D. Specific rotation of \(\alpha\)-anomer is \(+19^\circ\) while for \(\beta\)-anomer is \(+112^\circ\).
E. \(\alpha\) and \(\beta\) anomers of glucose are prepared by crystallization of saturated glucose solution at \(303 \text{ K}\) and \(371 \text{ K}\) respectively.