List of top Chemistry Questions

Which of the following is used as froth stabilizer in froth floatation process?
The equation which represents Freundlich adsorption isotherm is (x = amount of gas, m = mass of solid)
An element (atomic weight = 250 u) crystallises in a simple cubic lattice. If the density of the unit cell is \( 7.2 \, \text{g cm}^{-3} \), what is the radius (in \( \text{\AA} \)) of the atom of the element? (\(N = 6.02 \times 10^{23} \, \text{mol}^{-1}\))
Compound 'X' is prepared commercially by the electrolysis of brine solution. Which of the following is not the use of 'X'?
Identify the incorrect order against the stated property.
Consider the following Statement-I : \( \text{Al}_2\text{O}_3 \) is amphoteric in nature. Statement-II : \( \text{Tl}_2\text{O}_3 \) is more basic than \( \text{Ga}_2\text{O}_3 \). The correct answer is
Consider the following A) 0.0025 B) 500.0 C) 2.0034 Number of significant figures in A, B and C respectively, are
At \(25 ^\circ\text{C}\), \(K_a\) of formic acid is \(1.8 \times 10^{-4}\). What is the \(K_b\) of \( \text{HCOO}^- \)?
The pair of molecules / ions with the same bond order value is
The correct order of the non-metallic character among the elements B, C, N, F and Si is
How many of the following molecules have two lone pairs of electrons on central atom? SF\(_6\), BF\(_3\), ClF\(_3\), PCl\(_5\), BrF\(_5\), XeF\(_4\), H\(_2\)O, SF\(_4\)
Match the following polymers with their applications: \begin{center} \begin{tabular}{|c|c|} \hline List-I (Polymer) & List-II (Used in making)
\hline
Match the following polymers with their applications:
The adsorption of a gas on a solid surface follows Freundlich adsorption isotherm. At \( T \)(K), the gas pressure is \( 2 \) atm. What is the value of \( \frac{x}{m} \)? (\( n = 2 \) and \( k \) = constant)
In which one of the following complexes the metal ion has \( t_{2g}^3 e_g^2 \) configuration?
Consider the following: Statement-I: In the extraction of Al by Hall-Heroult process, pure \( Al_2O_3 \) mixed with \( Na_3AlF_6 \) lowers its melting point and increases conductivity. Statement-II: Zirconium metal is purified by zone refining method. The correct answer is:
Which of the following is not correct?
The composition of a sample of wustite is \( \text{Fe}_{0.93} \text{O}_{1.00} \). Percentage of iron in the form of \( \text{Fe}^{3+} \) ion is nearly:
The correct order of density of Be, Mg, Ca, Sr is:
Match the following pollutant concentration limits in water with their effects:
Consider the following gaseous equilibrium reactions (I), (II) and (III) with equilibrium constants \( K_1 \), \( K_2 \), and \( K_3 \) respectively:
I) \( \frac{1}{2} N_2 + \frac{3}{2} H_2 \rightleftharpoons NH_3 \)
II) \( 2NO \rightleftharpoons N_2 + O_2 \)
III) \( H_2 + \frac{1}{2} O_2 \rightleftharpoons H_2O \)
The correct expression for the equilibrium constant for the gaseous equilibrium reaction: \[ 2NH_3 + \frac{5}{2} O_2 \rightleftharpoons 2NO + 3H_2O \]
Which set of elements form electron-precise hydrides?
Identify the reaction in which diborane is produced on an industrial scale:
At \( 27^\circ C \) kinetic energy of 4 g of \( H_2 \) is \( x \) J. What is the kinetic energy (in J) of 6.4 g of oxygen at \( 127^\circ C \)?
The sum of bond order values of \( C_2 \) and \( O_2^{2-} \) is \( x \), which is equal to the sum of bond order values of \( a, b, \) and \( c \). What are \( a, b, \) and \( c \)?