List of top Chemistry Questions

One mole of aqueous $ \text{SO}_3^{2-} $ is completely reacted with 2 moles of $ \text{Br}_2 (l) $. What is the oxidation state (s) of S in the product formed?
At T (K), a closed vessel containing 2 g of an ideal gas (A) (molar mass = $ M_A $) exerted a pressure of 1 atm. When 16 g of another ideal gas (B) (molar mass = $ M_B $) was introduced into this vessel, the pressure increased to 2 atm. What is the correct relationship between $ M_A $ and $ M_B $?
A flask with open mouth containing air was heated from 27°C to 477°C. Some air was expelled. What is the fraction of air expelled out?
Which of the following reactions are endothermic and spontaneous?
If the standard enthalpy change and entropy change of a reaction at 298 K are 11.1 kJ mol$^{-1}$ and 42 J K$^{-1}$ mol$^{-1}$, which one of the following options is correct?
1 L of 0.1 M HCl is added to 1 L of 0.1 M HA (weak acid) solution. To this solution, 16 g of solid NaOH is added. What is the pOH value of resultant solution? (Given molar mass of NaOH is 40 g/mol, $ \log 2 = 0.3, \log 4 = 0.6 $)
Chemistry of lanthanides ($ \text{Ln} $) is dominated by +3 oxidation state. Which of the following is incorrect?
Which of the following species has an unpaired electron?
If $ n $ is the principal quantum number, as per quantum mechanical model of atom, the maximum number of electrons possible in any energy level is limited to
The atomic mass of H and C is 1 and 12 u respectively. What is the ratio of weight of one atom each of H and C?
Which of the following molecules is not linear?

A disaccharide X cannot be oxidised by bromine water. The acid hydrolysis of X leads to a laevorotatory solution. The disaccharide X is

Which one of the following will undergo Nucleophilic substitution, by $S_N^1$ mechanism, fastest?
The reaction taking place in a galvanic cell is as given
A(s) + B\textsuperscript{2+} (11100\textsuperscript{-3}M) $\rightarrow$ B(s) + A\textsuperscript{2+} (0.1M)
The emf of the cell is +2.651 V. If the standard emf of the cell is +2.71 V, what is the value of X?
The reactions taking place with 2 - Phenyl - 2 - bromopropane as the starting material is shown below. Identify [A] and [B] formed in the reaction.
C\textsubscript{6}H\textsubscript{5} - C(Br)C\textsubscript{2}H\textsubscript{5} \xrightarrow{\text{KOH Alcoholic}} [A]
[A] + HBr $\to$ [B]
Identify the incorrect statement.
What would be the final product [X] formed when p-Toluene undergoes the following series of reactions?
Arrange the following in the decreasing order of their Dipole moments.
The energy of an electron in the ground state of Hydrogen atom is $-2.18 \times 10^{-18}$ J. What would be the energy associated with the second excited state of Li$^+$?
Which one of the following Coordination entities exhibits Facial and Meridional isomerism?
Choose the incorrect statement regarding Cellulose.
A gas taken in a closed vessel is heated from 54°C to 1254°(C) The pressure of the gas becomes __________ times its original pressure \( P_1 \).
If the depression in freezing point of an aqueous solution containing a solute, which is neither dissociated nor associated, is $aK$ with $K_f = b \ \text{K} \cdot \text{kg mol}^{-1}$, what would be the elevation in boiling point ($X$) for this solution if its $K_b = K \ \text{K} \cdot \text{kg mol}^{-1}$?
Which one of the following correctly represents the decreasing order of acidic nature of the given carboxylic acids:
[A] 2-Hydroxybenzoic acid
[B] Benzoic acid
[C] 3-Hydroxybenzoic acid
[D] 4-Hydroxybenzoic acid

Find the correct matches of the substances, given in Column I, from their characteristic properties given in Column II.