List of top Chemistry Questions

A reaction is second order with respect to a reactant. How is the rate of reaction affected if the concentration of the reactant is
(i) doubled
(ii) reduced to half?

The chemical inertness of $N_2$ is attributed to

The ratio of the velocities of

{C H}_{4}

and

O_{2}

molecules, so that they are associated with de-Broglie waves of equal wavelength is:

Compare the stability of +2 oxidation state for the elements of the first transition series

The moiety present at the 5' end of ribose sugar in a polynucleotide is

How is 1-propoxypropane synthesised from propan-1-ol?Write mechanism of this reaction.

Differentiate between the principle of estimation of nitrogen in an organic compound by (i) Dumas method and (ii) Kjeldahl’s method.

0.3780 g of an organic chloro compound gave 0.5740 g of silver chloride in Carius estimation. Calculate the percentage of chlorine present in the compound.

Justify giving reactions that among halogens, fluorine is the best oxidant and among hydrohalic compounds, hydroiodic acid is the best reductant.

In any period, the valency of an element with respect to oxygen

A solution is obtained by mixing 300 g of $25\%$ solution and 400 g of $40\%$ solution by mass. Calculate the mass percentage of the resulting solution.

How many mL of 0.1 M HCL are required to react completely with 1g mixture of $\text{Na}_2\text{CO}_3$ and $\text{NaHCO}_3$ containing equimolar amounts of both?

A solution of glucose in water is labelled as $10\%$ $\text{w/w}$, what would be the molality and mole fraction of each component in the solution? If the density of solution is $1.2\, \text{g mL}^{–1}$, then what shall be the molarity of the solution?

Concentrated nitric acid used in laboratory work is $68\%$ nitric acid by mass in aqueous solution. What should be the molarity of such a sample of the acid if the density of the solution is $1.504\, \text{g mL}^{–1}?$

Give an example of a solid solution in which the solute is a gas.

Apart from tetrahedral geometry, another possible geometry for CH₄is square planar with the four H atoms at the corners of the square and the C atom at its centre. Explain why CH₄is not square planar?

Explain with the help of suitable example polar covalent bond.

How much electricity is required in coulomb for the oxidation of
(i) 1 mol of H₂O to O₂.
(ii) 1 mol of FeO to Fe₂O₃.

How much electricity in terms of Faraday is required to produce
(i) 20.0 g of Ca from molten CaCl₂.
(ii) 40.0 g of Al from molten Al₂O₃.

Conductivity of 0.00241 M acetic acid is 7.896 × 10^-5 S cm^-1 . Calculate its molar conductivity and if $\land^0_m$ for acetic acid is 390.5 S cm² mol^-1 , what is its dissociation constant?

The resistance of a conductivity cell containing 0.001M KCl solution at 298 K is 1500 Ω. What is the cell constant if conductivity of 0.001M KCl solution at 298 K is 0.146 x 10^-3 S cm^-1 .

Define conductivity and molar conductivity for the solution of an electrolyte. Discuss their variation with concentration.

Calculate the standard cell potentials of galvanic cells in which the following reactions take place:
(i) $2Cr_{(S)}+3Cd^{2+}_{(aq)} \rightarrow 2Cr^{3+}_{(aq)}+3Cd$
(ii) $Fe^{2+}_{(aq)}+Ag^+_{(aq)} \rightarrow Fe^{3+}_{(Aq)}+Ag(s)$
Calculate the $\triangle_rG^\ominus$ and equilibrium constant of the reactions.

Given the standard electrode potentials,
K⁺/K = -2.93V, Ag⁺/Ag = 0.80V,
Hg²⁺/Hg = 0.79V
Mg²⁺/Mg = -2.37 V, Cr³⁺/Cr = - 0.74V
Arrange these metals in their increasing order of reducing power.

Arrange the following metals in the order in which they displace each other from the solution of their salts.
Al, Cu, Fe, Mg and Zn