List of top Chemistry Questions

An atom of an element contains 29 electrons and 35 neutrons. Deduce (i) the number of protons and (ii) the electronic configuration of the element.

An electron is in one of the 3d orbitals. Give the possible values of n, l and ml for this electron.

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.

What is the lowest value of n that allows g orbitals to exist?

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?

Explain why \(BeH_2\) molecule has a zero dipole moment although the \(Be-H\) bonds are polar

Calculate the number of atoms in each of the following:

1. 52 moles of Ar
2. 52 u of He
3. 52 g of He.

Although both \(CO_2\) and \(H_2O\) are triatomic molecules, the shape of \(H_2O\) molecule is bent while that of \(CO_2\) is linear. Explain this on the basis of dipole moment.

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å. Calculate the threshold frequency (ν₀) and work function (W₀) of the metal.

Define the bond length.

Use the data given in the following table to calculate the molar mass of naturally occuring argon isotopes:

Isotope	Isotopic molar mass	Abundance
36Ar	35.96755 g mol–1	0.337%
38Ar	37.96272 g mol–1	0.063%
40Ar	39.9624 g mol–1	99.600%

The conductivity of sodium chloride at 298 K has been determined at different concentrations and the results are given below: 
Concentration/M 0.001 0.010 0.020 0.050 0.100 
10²  × κ/S m^-1  1.237 11.85 23.15 55.53 106.74 
Calculate \(\land_m\) for all concentrations and draw a plot between \(\land_m\) and c ½. Find the value of  \(\land^0_m\).

How do you express the bond strength in terms of bond order?

Write the favourable factors for the formation of ionic bond.

How many significant figures should be present in the answer of the following calculations?

1. \(\frac {0.02856 × 298.15 × 0.112}{0.5785}\)
2. \(5 × 5.364\)
3. \(0.0125 + 0.7864 + 0.0215\)

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 .

The conductivity of 0.20 M solution of KCl at 298 K is 0.0248 Scm^-1 . Calculate its molar conductivity.

What will be the mass of one \(^{12}C\) atom in g?

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

Calculate the molarity of a solution of ethanol in water, in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).