List of top Chemistry Questions

Benzene diazonium chloride on treatment with hypophosphorous acid and water yields benzene. Which of the following is used as a catalyst in this reaction?
The reaction between COOH and NaHCO\(_3\) is:
The basic structural unit of silicates is
A magnetic moment of 1.73 BM will be shown by one among the following
XeF2 is isostructural with
Which of the following is electron-deficient?
Which one of the following molecules contains no π bond ?
Which of the following is a polar molecule ?
Which of the following is paramagnetic ?
Reaction by which Benzaldehyde cannot be prepared
The structure of isobutyl group in an organic compound is
Which of the following compounds will not undergo Friedal-Craft's reaction easily?
The radical Chemical Structure is aromatic because it has
Among the following four structures $I$ to $IV$, it is true that
Figure shows a copper rod joined to a steel rod. The rods have equal length and equal crosssectional area. The free end of the copper rod is kept at $0^{\circ} C$ and that of steel rod is kept at $100^{\circ} C$. Find the temperature of the junction of the rod. Conductivity of copper $=390 W / m ^{\circ} C$. Conductivity of steel $=46 W / m ^{\circ} C$
When same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide solution, the ratio of volumes of hydrogen evolved is:
The enthalpy of combustion of $2$ moles of benzene at $27^{\circ} C$ differs from the value determined in bomb calorimeter by
The oxidation state of sulphur in $Na_2S_4O_6$ is
KMnO4 can be prepared from K2MnO4 as per the reaction:
\(3MnO^{2-}_4+2H_2O⇌2MnO^-_4+MnO_2+4OH^-\)
The reaction can go to completion by removing OH- ions by adding
Which of the following lanthanoid ions is diamagnetic ?
(At. nos. Ce = 58, Sm = 62, Eu = 63, Yb = 70)
A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of electrode would be
For the dissociation reaction, $H _{2}( g ) \rightarrow 2 H ( g ) \quad \Delta H =162 Kcal$, heat of atomisation of $H$ is
What is the activation energy for a reaction if its rate doubles when the temperature is raised from 20°C to 35°C ? (R = 8.314 J mol-1 K-1)
The alkali metals form salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following order?
Nylon is an example of