List of top Chemistry Questions

For a spontaneous process at constant temperature and pressure, which of the following is true?
For a first-order reaction, the time required to reduce the concentration of the reactant to one-fourth of its initial value is 20 minutes. What is the half-life of the reaction?
Which of the following gases will deviate most from ideal behavior at high pressure?
Sucrose when boiled with dilute HCl gives two functional isomers X and Y. X gives monocarboxylic acid with bromine water but not Y. The number of --OH groups in cyclic structure of X is
Consider the following
Statement-I: Natural rubber becomes soft at low temperature and brittle at high temperature.
Statement-II: Natural rubber has weak van der Waals forces between its polymer chains.
The water soluble vitamin which is not excreted through urine easily is
Identify the artificial sweetener which has highest sweetness value compared to cane sugar
Identify the complex ion/s with the least spin only magnetic moment (in BM).
I) [Fe(CN)$_6$]$^{3-}$
II) [Co(CN)$_6$]$^{3-}$
III) [Mn(CN)$_6$]$^{4-}$
IV) [Fe(CN)$_6$]$^{4-}$
Alkaline oxidative fusion of MnO$_2$ gives 'X'. The products formed when 'X' undergoes disproportionation in acid medium are
I) KMnO$_4$
II) MnO$_2$
III) O$_2$
IV) H$_2$O
Identify the reaction which occurs in blast furnace at temperature of above 900 K.
The number of monochloro derivatives possible for 2,2-Dimethylbutane and 2,3-Dimethylbutane are respectively
The osmotic pressure of 0.01 molar solution of an electrolyte is found to be 0.65 bar at 27°C. The van’t Hoff factor of the electrolyte is (R = 0.083 bar L K$^{-1}$ mol$^{-1}$)
The conjugate acid and base of ammonia are X and Y, respectively. What are the shapes of X and Y?
For the reactions: NaBH$_4$ + I$_2$ $\rightarrow$ A + NaI + H$_2$, and A + LiH $\rightarrow$ B, what are A and B, respectively? (Reactions are not balanced)
The buffer system that helps in maintaining pH of blood between 7.26 and 7.42 is
Vessel (A) contains 1 mole each of H$_2$ and I$_2$, and vessel (B) contains 2 moles each of H$_2$ and I$_2$. Both vessels are at the same temperature and reach equilibrium for the reaction H$_2$(g) + I$_2$(g) $\rightleftharpoons$ 2HI(g). What is the ratio of the equilibrium constants $K_p$ for vessels A and B?
The BOD value of clean water is X. The maximum concentration of cadmium recommended in drinking water is Y. X and Y respectively are
Observe the following molecules: ClF, SF$_4$, CH$_4$, NH$_3$, XeF$_4$, PCl$_5$. The number of molecules in which the central atom has expanded octet is:
One mole of an ideal gas is contained in a 1 L vessel at T(K) with a pressure of p atm. The vessel is split into two equal parts. What are the pressure and volume in each part?
The sum of number of antibonding electrons present in O$_2$, O$_2^+$, O$_2^-$ is:

For hydrogen-like species, which of the following graphs provides the most appropriate representation of \( E \) vs \( Z \) plot for a constant \( n \)?
[E : Energy of the stationary state, Z : atomic number, n = principal quantum number]

Identify the amide which gives propan-1-amine by Hoffmann bromamide reaction.
What are X and Z in the following reaction sequence? (X forms sodium alkynide) \[ X (C_4H_6) \xrightarrow{{partial reduction}} Y \xrightarrow{H_2O/H^+} Z ({major product}) \]
Which of the following compounds give salt of an acid and alcohol on heating with concentrated KOH?
What is Z in the given reaction sequence? \[ {(1) } B_2H_6 \longrightarrow X \xrightarrow{PCC} Y \xrightarrow{NH_2OH} Z \] \[ {(2) } H_2O, H_2O_2, OH^- \]