List of top Chemistry Questions

An ideal gas expands against a constant external pressure of 2.0 atmosphere from 20 litre to 40 litre and absorbs 10 kJ of heat from the surrounding. What is the change in internal energy of the system? (given: \( 1 \, {atm-litre} = 101.3 \, {J} \))

The limiting equivalent conductivity of NaCl, KCl, and KBr are \( 126.5 \), \( 150.0 \), and \( 151.5 \) S cm\(^2\) eq\(^{-1}\), respectively. The limiting equivalent ionic conductivity for Br\(^{-}\) is \( 78 \) S cm\(^2\) eq\(^{-1}\). The limiting equivalent ionic conductivity for Na\(^+\) ions would be:

Bauxite ore is generally contaminated with impurity of oxides of two elements X and Y. Which of the following statement is correct?

The shape of \([ \text{Cu}(\text{NH}_3)_4 ]^{2+}\) is:

The form of iron obtained from blast furnace is:
Lyophilic sols are more stable than lyophobic sols because:
The oxidation number of phosphorus in \( {Ba(H}_2{PO}_2)_2 \) is:
200 mL of an aqueous solution of a protein contains 1.26 g. The osmotic pressure of this solution at 300 K is found to be \( 2.57 \times 10^{-3} \, {bar} \). The molar mass of the protein will be: (R = 0.083 L bar mol\(^{-1}\) K\(^{-1}\))
The value of van der Waals constant ' a ' for gases \( {O}_2 \), \( {N}_2 \), \( {NH}_3 \), and \( {CH}_4 \) are 1.360, 1.390, 4.170, and 2.253 L\(^2\)atm/mol\(^2\) respectively. The gas which can most easily be liquefied is:

Molar conductance of monobromoacetic acid at infinite dilution is calculated to be \( x \times 10^{-4} \, \text{S m}^2 \, \text{mol}^{-1} \) \(\text{at 25°C.} \)The value of \( x \) is (round off to the nearest integer).

Consider the following reaction:
The CORRECT pathway(s) involved in the reaction is/are
A 16 mW monochromatic light emits \( 4 \times 10^{16} \) photons in 1 second. When this light incident on a metal strip, photoelectrons are emitted. The wavelength of the emitted photoelectrons (in Å) is ________ (round off to one decimal place).
Consider the following reaction:
The CORRECT statement(s) related to mono-chlorination at carbon-2 position is/are
The equilibrium constant for isomerization of 1-butene to trans-2-butene at 27°C is ________ (round off to one decimal place).
The total number of 3-centre-2-electron bonds in \( B_4H_{10} \) is ________. (in integer).
An aqueous solution of aspirin (HA) is prepared at pH 7.4. The ratio of concentration of \( \text{A}^- \) and \( \text{HA} \) at equilibrium is ________. (round off to the nearest integer).
The CORRECT order of basicity for the following compounds is
A sample of benzene, contaminated with a non-volatile and non-ionic solute, boils at 0.31°C higher than that of pure benzene. The molality of the solute in the contaminated solution is ________ (round off to two decimal places).
Among the following statements about cobalt complexes, which is/are CORRECT? Given: Atomic number of Co is 27
Which among the following metal ions has the highest enthalpy of hydration? (Assume the given metal ions have the same counter ion.) Given: Atomic numbers of Ti, V, Cr and Mn are 22, 23, 24 and 25, respectively.
Consider a second order reaction, \( 2A \rightarrow \text{Product} \).
The concentration of A is represented as \( [A] \).
Which of the following is the CORRECT plot for determining the rate constant for the above reaction?
Among the following, the one having smallest bond angle is
Which among the following has the least second ionization energy?
Which of the following lanthanides are in tv screen.
Lanthanoid contraction can be observed in: