List of top Chemistry Questions

The conjugate base of NH$_4^+$ is
The major product ‘B’ of the following reaction sequence is
major product ‘B’ of the following reaction sequence is
Which of the following compounds do not have sp$^3$ carbon atom(s)?
I. Acetone\quad II. Acetic acid\quad III. Buta-1,3-diene\quad IV. Propyne\quad V. Naphthalene
The percentage of abundance of three elements X, Y and Z in the earth’s crust are about 27.7, 8.3 and 46.0 by mass respectively. X, Y and Z are
The two stable isotopes of carbon present in the naturally occurring carbon are
Which of the following conditions are not suitable for a spontaneous reaction?
Which of the following does not show disproportionation reaction?
For the formation of NH$_3$(g) from its constituent elements, which of the relation between the reaction quotient (Q) and equilibrium constant (K$_c$) is correct for the backward reaction?
Among the ions O$^{2-}$, Na$^+$, F$^-$, N$^{3-}$, Mg$^{2+}$ the ions with smallest and largest radii are respectively
The ratio of rate of diffusion of SO$_2$ to CH$_4$ is
The ratio of radii of second orbit of hydrogen atom to fourth orbit of He$^+$ ion is
The velocity of the electron in Bohr’s first orbit is \( x \times 10^6 \, \text{ms}^{-1} \). The deBroglie wavelength associated with it (in nm) is (Given: \( m_e = 9 \times 10^{-31} \, \text{kg}, \, h = 6.6 \times 10^{-34} \, \text{Js} \))
The molecule which has more number of lone pair of electrons than the bond pair of electrons in its central atom is
Arrange the following in the correct order of their bond orders: N$_2$, O$_2$, O$_2^+$, O$_2^-$
The frequency band for uplink satellite communication in the following is
Consider the following statements
Statement (A): The resistance of an ideal diode in forward biased condition is zero.
Statement (B): In a half wave rectifier, the load current flows only for every half cycle of the input signals.
Statement (C): In the breakdown region, a zener diode behaves as a constant voltage source.
The element with the electronic configuration [Kr]4d$^{10}$5s$^0$ is
A light from Paschen series of hydrogen atom is able to eject photoelectrons from a metal. Then the work function of the metal is
The correct statement of the following is
What are the oxidation states of the three Br atoms in the molecule \( \mathrm{Br_3O_6} \)?
The bond lengths of \( \mathrm{C_2} \), \( \mathrm{N_2} \), and \( \mathrm{B_2} \) molecules are \( X_1 \), \( X_2 \), and \( X_3 \) pm respectively. The correct order of their bond lengths is:
Identify A and B from the following reaction:\ NaNO3(\xrightarrow{\Delta}\) xA + yB
Assertion (A): MgSO4 is readily soluble in water.
Reason (R): The greater hydration enthalpy of Mg2+ ions overcomes its lattice enthalpy.
At T (K), x g of a non-volatile solid (molar mass 78 g mol$^{-1}$) when added to 0.5 kg water, lowered its freezing point by 1.0°C. What is x (in g)? (K$_f$ of water at T(K) = 1.86 K kg mol$^{-1}$)
The rate constant for a zero order reaction A → products is 0.0030 mol L$^{-1}$ s$^{-1}$. How long will it take for the initial concentration of A to fall from 0.10 M to 0.075 M?