List of top Chemistry Questions asked in COMEDK UGET

A current of 2.5 amperes is passed through 800 ml of 0.48 M solution of CuSO$_4$ for 1.0 hour with a current efficiency of 80%. If the volume of the solution remains unchanged, what is the final molarity of the solution?

If \(X\) is a haloalkane with a single chlorine atom per molecule and the percentage of Cl is 55, what would be the number of Cl atoms present in 0.1 g of the haloalkane? Atomic mass of Cl = 35.5 g/mol

From the given covalent compounds (A to F) identify the pair of molecules which have:
(i) Two lone pairs of electrons on the central atom.
(ii) One lone pair of electrons on the central atom.
A. \(SO_2\)
B. \(ClF_3\)
C. \(BF_3\)
D. \(BrF_5\)
E. \(XeF_4\)
F. \(SF_6\)

An organic compound [X] reacts with \(H_2/Pd-BaSO_4\) to give compound [Y], which reduces Tollens' reagent and undergoes Cannizzaro's reaction. On rigorous oxidation of [Y] in presence of \(KMnO_4/H^+\), phthalic acid is the product obtained. What is [X]?

A certain orbital having 2 angular nodes and no radial nodes is:

Arrange the following free radicals in the increasing order of their stability:

Two chemical reactions of the same order have equal frequency factor value. Their activation energies differ by 26.8 kJ/mol. At 300 K if \(k_2 = xk_1\), find the value of \(x\).

Choose the incorrect statement.

Both reactions (i) and (ii) give the same compound \(X\) as the major product. Identify \(X\).
\[ \text{(i) } 3\text{-Methylbut-1-ene} + HCl \rightarrow X \] \[ \text{(ii) Neopentyl alcohol} + HCl \ (\text{anh. } ZnCl_2) \rightarrow X \]

Solubility product of the sparingly soluble salt \(AgBrO_3\) in aqueous medium is \(9.3 \times 10^{-10}\). Calculate the mass in gram of \(AgBrO_3\) present in \(100 \, ml\) of its saturated solution. (Molar mass of \(AgBrO_3 = 236 \, g \, mol^{-1}\))

Arrange the following compounds in the decreasing order of the molar conductivities of their aqueous solutions.

What is the reduction potential of a half-cell consisting of a Pt electrode dipped in \(2.2M\ Fe^{2+}\) and \(0.04M\ Fe^{3+}\) solution where the reaction taking place is conversion of \(Fe^{3+}\) ions to \(Fe^{2+}\)? Given \(E^\circ(Fe^{3+}/Fe^{2+})=0.771\ V\)

Identify the correct statement.
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A non-volatile solute A weighing \(60 \, g\) when dissolved in \(212 \, g\) of the solvent xylene reduces its vapour pressure to \(60\%\). What is the molar mass of A in \(g \, mol^{-1}\)? Given molar mass of xylene \(= 106 \, g \, mol^{-1}\).

What is the final product \([Z]\) formed when the given reactions take place?

For a 1.0 molal solution containing the non-volatile solute urea, the elevation in boiling point is 2.0 K while the depression in freezing point in a 3.0 molal solution having the same solvent is 4.0 K. If the ratio \( \frac{K_b}{K_f} = \frac{1}{X} \), what is the value of \(X\)?

Two statements, one Assertion (A) and the other Reason (R) are given. Choose the correct option. Assertion: Compound \([X]\) reacts with hydrazine in presence of \(KOH/Glycol\) to form the product \([Y]\). Reason: Reduction reaction occurs and carbonyl group is reduced to methylene group.

The concentration and percentage purity of oxalic acid can be determined by titration with \(KMnO_4\) in presence of dil. \(H_2SO_4\). Instead of dil. \(H_2SO_4\), dil. HCl cannot be used because

Which of the following haloalkanes will give more than one isomeric product, on being heated with alc. KOH?

Two statements, one Assertion (A) and the other Reason (R) are given. Choose the correct option. Assertion: The rate constant (\(k\)) for a chemical reaction gets nearly doubled for a \(10^\circ\) rise in temperature. Reason: The number of bimolecular collisions between reactant molecules increases with increase in temperature.

An organic compound [X] (molecular formula \(C_5H_{11}NO\)) when reacted with \(Br_2/\text{aq. NaOH}\) yielded [Y] which reacts with \(CHCl_3\) and ethanolic KOH to produce a foul smelling compound. Compound [Y] also reacts with HONO to produce Butan-1-ol with liberation of \(N_2(g)\). Identify [X].

Which one of the following coordination compounds will exhibit both geometrical and optical isomerism?

Choose the correct statement.

Which one of the following is a true statement with reference to reaction between 2-Bromo-2-methylpropane and aqueous KOH?

Convert Benzene \(\rightarrow\) 3-Bromophenol by choosing appropriate reagents (i) to (v) in the correct sequence.
\[ \text{(i) } NaNO_2/HCl \, (0^\circ C) \] \[ \text{(ii) Conc. } HNO_3/H_2SO_4 \] \[ \text{(iii) } H_2O/283 \, K \] \[ \text{(iv) } Fe/HCl \] \[ \text{(v) } Br_2/Fe \]