List of top Chemistry Questions

Elements A and B form two non-volatile compounds (AB$_2$ and AB$_4$). When 1 g of AB$_2$ is added to 20 g of C$_6$H$_6$ (molar mass =78 gmol$^{-1}$) the freezing point of C$_6$H$_6$ is lowered by 2.3 K. When 1 g of AB$_4$ is added to 20 g of C$_6$H$_6$, the freezing point of C$_6$H$_6$ was lowered by 1.3 K. The atomic masses of A and B are respectively (K$_f$(C$_6$H$_6$)=5.1 K kg mol$^{-1}$)
Neoprene is the polymer of a monomer X. IUPAC name of X is
The products C and D are
The reaction/s which represent the production of diborane on an industrial scale is/are:
I. 4BF$_3$ + 3LiAlH$_4$ → 2B$_2$H$_6$ + 3LiF + 3AlF$_3$
II. 2NaBH$_4$ + I$_2$ → B$_2$H$_6$ + 2NaI + H$_2$
III. 2BF$_3$ + 6NaH → B$_2$H$_6$ + 6NaF
X and Y in reaction sequence:
The IUPAC name of the following compound is
Consider the following statements
Statement-I: Oxides of sulphur and nitrogen are air pollutants
Statement-II: Photochemical smog is a reducing smog
The correct answer is
In which of the following, intramolecular hydrogen bonding is present?
Match the following
The correct answer is
What are X, Y, Z respectively in the following reaction sequence?
CH$_3$CH=CHCH$_3$ $\xrightarrow{X}$ CH$_3$COOH $\xrightarrow{Y}$ CH$_3$CO-Cl $\xrightarrow{Z, C6H5NH2}$ C$_6$H$_5$NHCOCH$_3$
Identify the correct statements from the following
I. In Leclanché cell, Mn$^{2+}$ is oxidized to Mn$^{3+}$
II. Electrolysis of aqueous CuCl$_2$ solution using Pt electrodes liberate Cl$_2$ (g) at anode
III. Lead storage battery is a secondary battery
The sum of bond order of \(O_2\), \(O_2^-\), \(O_2^{2-}\) and \(O_2^+\) is equal to
An alkyne has the molecular formula C₆H₁₀. The number of 1-alkyne isomers (excluding stereoisomers) possible for it is
According to Bohr's theory of hydrogen atom, the approximate angular momentum of electron in H atom in the ground state is ($h = 6.62 \times 10^{-34}$ Js):
The reagent which is used to distinguish primary, secondary and tertiary amines from the mixture is
The energy associated with electron in first orbit of hydrogen atom is \(-2.18 \times 10^{-18}\) J. The frequency of the light required (in Hz) to excite the electron to fifth orbit is (\(h=6.6 \times 10^{-34}\) Js)
The source of an enzyme is malt and that enzyme converts X into Y. X and Y respectively are
Change in oxidation state of sulphur during oxidation of thiosulphate ion in neutral/alkaline solution by KMnO$_4$ is:
Which one of the following mixtures can be separated by steam distillation technique?
At T(K) 10 L of an ideal gas was expanded to 12 L against a pressure of 2 atm irreversibly. What is the work done by the gas?
X and Y in reactions:
The incorrect statement about Castner-Kellner cell process is
Among alkaline earth metals, metal with least melting point is:
An alcohol X (C$_4$H$_{10}$O) reacts with Conc.HCl/ZnCl$_2$ to give corresponding chloride. X on dehydration forms Y, which reacts with Baeyer's reagent to give Z. What is Z?
Identify the incorrect match