COMEDK 2023 Morning Shift

Product of the following reaction is

Acetophenone when reacted with a base, \(\mathrm{C}_2 \mathrm{H}_5 \mathrm{ONa}\), yields a stable compound which has the structure

Which of the following is incorrect?

Bohr's radius of 2 nd orbit of \(\mathrm{Be}^{3+}\) is equal to that of

The ion that is isoelectronic with \(\mathrm{CO}\) is

Which of the following hexoses will form the same osazone when treated with excess phenyl hydrazine?

Pick out the incorrect statement(s) from the following.
1. Glucose exists in two different crystalline forms, \(\alpha\)-D-glucose and \(\beta\)-D-glucose.
2. \(\alpha\)-D-glucose and \(\beta\)-D-glucose are anomers.
3. \(\alpha\)-D-glucose...

Which one of the following is an important component of chlorophyll?

Which of the following compounds would not be expected to decarboxylate when heated?

Which of these represents the correct order of decreasing bond order?

Pick up the correct statement.

Total number of \(\sigma\) and \(\pi\) bonds in ethene molecule is

Which of these molecules have non-bonding electron pairs on the cental atom?
\(\mathrm{I}: \mathrm{SF}_4 : \mathrm{II}: \mathrm{ICl}_3 : \mathrm{III}: \mathrm{SO}_2\)

Consider the following equilibrium,
$$\begin{aligned}
& 2 \mathrm{No}(g) \rightleftharpoons \mathrm{N}_2+\mathrm{O}_2 ; \mathrm{K}_{\mathrm{G}}=2.4 \times 10^{20} \\
& \mathrm{No}(\mathrm{g})+\frac{1}{2} \mathrm{Br}_2(\mathrm{~g}) \rightlef...

How much faster would a reaction proceed at \(25^{\circ} \mathrm{C}\) than at \(0^{\circ} \mathrm{C}\) if the activation energy is \(65 \mathrm{~kJ}\)?

At \(300 \mathrm{~K}\), the half-life period of a gaseous reaction at an initial pressure of \(40 \mathrm{~kPa}\) is 350 s. When pressure is \(20 \mathrm{~kPa}\), the half-life period is 175 s. What is the order of the reaction?

For a reaction, \(2 A+B \longrightarrow\) products,
If concentration of \(B\) is kept constant and concentration of \(A\) is doubled then rate of reaction is

A drug that is antipyretic as well as analgesic is

Oil of winter green is

Gabriel's synthesis is used frequency for the preparation of which of the following?

The product P in the reaction,

Which among the following is diamagnetic?

The complex \(\left[\mathrm{PtCl}_2(\mathrm{en})_2\right]^{2+}\) ion shows

The blue colouration obtained from the Lassaigne's test of nitrogen is due to the formation of

Aqueous \(\mathrm{CuSO}_4\) changes its colour from sky blue to deep blue on addition of \(\mathrm{NH}_3\) because

Which of the following complex show optical isomerism?
(i) \(c i s-\left[\mathrm{COCl}(\mathrm{en})_2\left(\mathrm{NH}_3\right)\right]^{2+}\)
(ii) \(cis-\left[\mathrm{CrCl}_2(\mathrm{ox})_2\right]^{3-}\)
(iii) $$cis-[ \left.\mathrm{CO}(\mat...

Mohr's salt has the formula

\(\mathrm{Ti}^{2+}\) is purple while \(\mathrm{Ti}^{4+}\) is colourless because

A volatile compound is formed by carbon monoxide and

Assuming no change in volume, the time required to obtain solution of \(\mathrm{pH}=4\) by electrolysis of \(100 \mathrm{~mL}\) of \(0.1 \mathrm{~M} \mathrm{~NaOH}\) (using current \(0.5 \mathrm{~A}\) ) will be

For a cell reaction, \(A(s)+B^{2+}(a q) \longrightarrow A^{2+}(a q)+B(s)\); the standard emf of the cell is \(0.295 \mathrm{~V}\) at \(25^{\circ} \mathrm{C}\). The equilibrium constant at \(25^{\circ} \mathrm{C}\) will be

Ozone in stratosphere is depleted by

Rank the following compounds in order of increasing basicity.

\(t\)-butyl chloride preferably undergo hydrolysis by

In Friedal-Crafts alkylation reaction of phenol with chloromethane, the product formed will be

Identify A, B and C.

Ammoniacal silver nitrate forms a white precipitate easily with

Decomposition of hydrogen peroxide can be prevented by adding

In a \(0.2 \mathrm{~M}\) aqueous solution, lactic acid is \(6.9 \%\) dissociated. The value of dissociation constant is

A buffer solution has equal volumes of \(0.1 \mathrm{~M} \mathrm{~NH}_4 \mathrm{OH}\) and \(0.01 \mathrm{~M} \mathrm{~NH}_4 \mathrm{Cl}\). The \(\mathrm{pK}_b\) of the base is 5. The \(\mathrm{pH}\) is

I and II are

Which of the following is incorrect regarding Henry's law?

Which of the following shows negative deviation from Raoult's law?

\(5 \mathrm{~g}\) of non-volatile water soluble compound \(X\) is dissolved in \(100 \mathrm{~g}\) of water. The elevation in boiling point is found to be 0.25. The molecular mass of compound \(X\) is

Abnormal colligative properties are observed only when the dissolved non-volatile solute in a given dilute solution

Given are \(\mathrm{H}_3 \mathrm{PO}_2, \mathrm{H}_3 \mathrm{PO}_3, \mathrm{H}_3 \mathrm{PO}_4\) and \(\mathrm{H}_4 \mathrm{P}_2 \mathrm{O}_7\). Which of the above oxacids results into two series of salts?

The order of acidic strength of boron trihalides is

The correct decreasing order of negative electron gain enthalpy for \(\mathrm{C}, \mathrm{Ca}, \mathrm{Al}, \mathrm{F}\) and \(\mathrm{O}\) is

Which one of the following is an example of step growth polymerisation?