List of top Questions asked in COMEDK UGET

Identify the pair of molecules in which one of them is a molecule with an odd electron and the other has an expanded octet.

In the estimation of element X in an organic compound, 0.8 g of the compound containing X was heated with fuming HNO₃ and the cooled product was treated with barium chloride. The mass of barium sulphate precipitated was 1.2 g. What is the percentage of element X and what is the formula of the violet-coloured compound formed when Lassaigne's extract of the organic compound is treated with sodium nitroprusside?

What is/are the product/s formed when Benzaldehyde and Ethanal react in the presence of dil. NaOH followed by heating the intermediate product formed?

Given are the names of 4 compounds. Two of these compounds will not undergo Cannizzaro's reaction. Identify the two.

Identify the product [C] formed at the end of the reaction below: $ 1,1,2,2-\text{Tetrabromopropane} + 2 \text{Zn (s)}/ \text{Ethanol} \rightarrow [B] $ $ [B] + 2 \text{moles of HBr} \rightarrow [C] $

Given below are 2 statements: Assertion and Reason. Choose the correct option.
Assertion: When Molar conductivity for a strong electrolyte is plotted versus $ \sqrt{C} \, (\text{mol/L})^{1/2} $, a straight line is obtained with intercept equal to Molar conductivity at infinite dilution for the electrolyte and slope equal to $ -A $. All electrolytes of a given type have the same $ A $ value.
Reason: At infinite dilution, strong electrolytes of the same type will have different numbers of ions due to incomplete dissociation.

What is the quantity of charge, in Faraday units, required for the reduction of 3.5 moles of $Cr_2\text{O}_7^{2-} \text{ in acid medium?}$

What are the Principal & Azimuthal quantum number values of the valence electrons in tripositive Lutetium?

An inorganic compound W undergoes the following reactions: $ W + \text{Na}_2\text{CO}_3 \xrightarrow{\text{O}_2 / \text{heat}} X + H^+ \xrightarrow{} Y(s) $ $ Y(aq) + \text{KCl} (aq) \xrightarrow{} Z(s) $ Z appears in the form of orange crystals and is used as an oxidising agent in acid medium. Identify the compound W.

Two statements, Assertion and Reason are given below. Choose the correct option.
Assertion: $ \text{n-propyl tert-butyl ether can be readily prepared in the laboratory by Williamson's synthesis.} $
Reason: The reaction occurs by $ S_N1 $ attack of Primary alkoxide on Tert-alkyl halide to give a good yield of the product, $ \text{n-propyl tert-butyl ether.} $

Identify the compound which is non-aromatic in nature.

Identify the correct statement from the following.

One of the reactions A, B, C, D given below yields a product which will not answer Hinsberg's test when reacted with Benzene sulphonyl chloride. Identify the reaction.

Identify the final product formed when Toluene undergoes a series of reactions with reagents given in the order:
(i) $ \text{Cl}_2 / \text{Sunlight} $
(ii) $ \text{H}_2\text{O}/373 \, \text{K} $
(iii) Acetophenone / $ \text{OH}^- $ at 293 K

4 statements are given below. Identify the incorrect statement:

(A) Phenol has lower $ pK_a $ value than $ \text{p} $-cresol.
(B) 2-Chlorophenol is more acidic than phenol.
(C) Ortho and para nitrophenols can be separated by steam distillation since $ \text{p} $-Nitrophenol is more steam volatile than $ o $-Nitrophenol.
(D) Phenol on reaction with $ \text{Cr}_2\text{O}_7^{2-} / \text{H}^+ $ yields a conjugated diketone.

Study the graph between partial pressure and mole fraction of some gases and arrange the gases P, Q, R, and S dissolved in H2O, in the decreasing order of their KH values.

A Hydrocarbon $ [A] $ (molecular formula $ C_3H_6 $) on reaction with $ \text{Br}_2/\text{CCl}_4 $ gave $ [B] $. When $ [B] $ is heated with 2 moles of alcoholic KOH, it gave compound $ [C] $. 3 moles of Compound $ [C] $ when passed through red hot Iron tube forms $ [D] $. Identify $ [D] $.

A compound having molecular formula $ C_4H_{11}N $, reacts with $ \text{CHCl}_3 $ in alcoholic KOH, on heating, to form a compound with a foul smell. Identify the optically active isomer of the compound which also shows the above reaction.

If $ A = \begin{bmatrix} 0 & x & 16 \\ x & 5 & 7 \\ 0 & 9 & x \end{bmatrix} $ is a singular matrix, then $ x $ is equal to

If the straight lines $ \frac{x - 2}{1} = \frac{y - 3}{1} = \frac{z - 4}{-t} \quad \text{and} \quad \frac{x - 1}{t} = \frac{y - 4}{2} = \frac{z - 5}{1} \quad \text{are intersecting, then $ t $ can have:} $

The sum of the order and degree of the differential equation $ \left( \frac{d^5y}{dx^5} \right) + 4 \left( \frac{d^4y}{dx^4} \right) + \left( \frac{d^3y}{dx^3} \right) = x^2 - 1 $

In the expansion of $ \left( \frac{1}{x} + x \sin x \right)^{10} $, the coefficient of the 6th term is equal to $ 7^7g $, then the principal value of $ x $ is.

The letters of the word "COCHIN" are permuted and all the permutations are arranged in alphabetical order as in an English dictionary. The number of words that appear before the word "COCHIN" is

For an examination a candidate has to select 7 questions from three different groups A, B and C. The three groups contain 4, 5 and 6 questions respectively. In how many different ways can a candidate make his selection if he has to select at least 2 questions from each group?

The function $ f(x) = \tan^{-1}(\sin x + \cos x) $ is an increasing function in.