List of top Chemistry Questions

Identify the ion (hydrated in solution) which is not correctly matched with its spin only magnetic moment (in BM) given in brackets:
A and B are ideal gases. At T(K), 2 L of A with a pressure of 1 bar is mixed with 4 L of B with a pressure of P\(_B\) bar in a 100 L flask. The pressure exerted by gaseous mixture is 0.1 bar. What is the value of P\(_B\) in bar?
Among the following compounds, which one is not responsible for the depletion of ozone layer?
The preferred reagent for the preparation of pure alkyl chloride from alcohol is
The sequence of reagents required to convert aniline to benzoic acid is:
Which of the following statements is not correct?
Which of the following is not an antibiotic?

Which of the following statements are correct regarding lithium and magnesium? 
I) They react slowly with water 
II) Their bicarbonates are solids 
III) Their chlorides are not soluble in ethanol 
IV) Their nitrates decompose easily on heating 
 

The number of amphoteric oxides from the following is
\(\mathrm{CO_2, GeO_2, SnO_2, PbO_2, CO, GeO, SnO, PbO}\)
When a metal surface is irradiated with light of frequency \( \nu \) Hz, the kinetic energy of emitted photoelectrons is \( x \) J. When the same metal is irradiated with light of frequency \( y \) Hz, the kinetic energy of emitted electrons is \(\frac{z}{3}\) J. What is the threshold frequency (in Hz) of the metal?
From the following identify the change in which electron gain enthalpy is positive. (g = gas phase):
1.84 g of a mixture of CaCO\(_3\) and MgCO\(_3\) is strongly heated to get a residue of 0.96 g. The percentage of CaCO\(_3\) in the mixture is
Consider the following:
Statement-I: If thermal energy is stronger than intermolecular forces, the substance prefers to be in gaseous state.
Statement-II: At constant temperature, the density of an ideal gas is proportional to its pressure.
The correct answer is
The IUPAC name of the complex shown below is:
K₃[Co(COₓ)₃]
The ratio of wavelengths of first line (\( n_2 = 3 \)) and second line (\( n_2 = 4 \)) of Balmer series of hydrogen spectrum is
The crystal system of a compound with cell dimensions \( a = 0.387 \), \( b = 0.387 \), \( c = 0.504 \text{ nm} \); \( \alpha = \beta = 90^{\circ} \) and \( \gamma = 120^{\circ} \) is
At 298 K, the following reaction takes place for a cell at the hydrogen electrode: \[ H^+(aq) + e^- \longrightarrow \frac{1}{2} H_2 (1 \text{ bar}) \] The solution pH is 10.0. What is the hydrogen electrode potential in volts? (\(\frac{2.303RT}{F} = 0.06\) V)
Consider the following
Assertion (A): Dipole moment of NF\(_3\) is lesser than NH\(_3\)
Reason (R): In NF\(_3\), the orbital dipole due to lone pair of electrons is in the opposite direction to the resultant dipole moment of the three N-F bonds.
The correct answer is:
A metal crystallizes with hcp packing. The total number of voids, total number of tetrahedral voids and total number of octahedral voids are shown as A, B and C respectively. A, B and C in 0.25 moles of metal are respectively ($N_A$ = Avogadro number).
The number of electrons with magnetic quantum number $m = 0$ in the elements with atomic numbers $Z = 24$ and $Z = 29$ are respectively

What are X and Y respectively, in the following set of reactions? 

At T(K), adsorption of a gas on surface of a solid follows Freundlich adsorption isotherm. A graph of \( \log \left( \frac{x}{m} \right) \) (on y-axis) and \( \log p \) (on x-axis) for this gas gave a straight line with slope = 2 and intercept = 1.5. What is the value of n ?
When 30 mL of 0.2 M \( NH_4OH \) is added to 30 mL of 2 M \( NH_4Cl \) solution. If the pH of the buffer formed is 8.2, what is the \( pK_b \) of \( NH_4OH \)?
What is the IUPAC name of the compound \( \text{CH}_3\text{CH}_2\text{COCH}_2\text{CH}_3 \)?
In compound (X), hyperconjugation is present and in (Y), resonance effect is present. What are X and Y, respectively?