List of top Chemistry Questions

In the $3^{rd}$ period, the first ionisation potential is of the order
In the periodic table, the period number corresponds to
A cross-linked polymer is
For Freundlich isotherm a graph of log $\frac {x}{m}$ is plotted against $log\, P$. The slope of the line and its y-axis intercept, respectively corresponds to
Butylated hydroxy toluene as a food additive acts as
Enthalpy of combustion of carbon to $CO _{2}$ is $-393.5 \,kJ \,mol ^{-1}$. What amount of heat will be released upon formation of $35.2 \,g$ of $CO _{2}$ from carbon and oxygen gas?
Which of the following compounds undergoes nitration more readily?
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:
Among the following four structures $I$ to $IV$, it is true that
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
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)
A magnetic moment of 1.73 BM will be shown by one among the following
XeF2 is isostructural with
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
Which of the following lanthanoid ions is diamagnetic ?
(At. nos. Ce = 58, Sm = 62, Eu = 63, Yb = 70)
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
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?
The radical Chemical Structure is aromatic because it has
Nylon is an example of
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of solution is
Which of the following is paramagnetic ?
Which of the following is less acidic among the given halogen compounds?