List of top Questions asked in JEE Main- 2023

\(\lim\limits_{x\rightarrow0}\left(\left(\frac{1-cos^2(3x)}{cos^3(4x)}\right)\left(\frac{sin^3(4x)}{(log_e(2x+1))^5}\right)\right)\)is equal to

Reaction of propanamide with $Br_2/KOH(aq)$ produces :
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: [CoCl(NH3)]2– absorbs at lower wavelength of light with respect to [Co(NH3)5(H2O) 3–
Reason R: It is because the wavelength of the light absorbed depends on the oxidation state of the metal ion.
In the light of the above statements, choose the correct answer from the options given below:
The mismatched combinations are
A. Chlorophyll - Co 
B. Water hardness - EDTA 
C. Photography - [Ag(CN)2]- 
D. Wilkinson catalyst - [(Ph3P)3 RhCl]  
E. Chelating ligand-D- Penicillamine
Match List-I with List-II :

List I

(Reagents Used)

 

List II

(Compound with Functional group detected)

AAlkaline solution of copper sulphate and sodium citrateI
BNeutral FeCl3 solutionII
CAlkaline chloroform solutionIII
DPotassium iodide and sodium hypochloriteIV

Choose the correct answer from the options given below :

What is the correct order of acidity of the protons marked A-D in the given compounds?
Acidity order

Which of the following compound is used as the antacid?
Major product 'P' formed in the following reaction is:
Major product 'P' formed in the following reaction is:
The density of the alkali metals is in the order:
The reaction representing the Mond process for metal refining is _________.
The standard electrode potential \((\frac{M^{3+}}{M^{2+}})\) for V, Cr, Mn & Co are –0.26 V, –0.41 V, +1.57 V and +1.97 V, respectively. The metal ions which can liberate H2 from a dilute acid are

For 1 mol of gas, the plot of pV vs. p is shown below. p is the pressure and V is the volume of the gas. What is the value of compressibility factor at point A?
Pv vs V graph

In Carius tube, an organic compound ‘X’ is treated with sodium peroxide to form a mineral acid ‘Y’. The solution of \(BaCl_2\), is added to ‘Y’ to form a precipitate ‘Z’. ‘Z’ is used for the quantitative estimation of an extra element. ‘X’ could be
Match List-I with List-II :
List-I (Species) List-II (Maximum allowed concentration in ppm in drinking water)
AF-I< 50 ppm
B\(SO^{2-}_4\)II< 5 ppm
C\(NO^-_3\)III< 2 ppm
DZnIV< 500 ppm

Choose the correct answer from the options given below :

The correct sequence of reagents for the preparation of Q and R is:
The correct sequence of reagents for the preparation of Q and R is:

Using column chromatography, mixture of two compounds ‘A’ and ‘B’ was separated. ‘A’ eluted first, this indicates ‘B’ has
Alkali metal from the following with least melting point is:
'X' is: 
X is:
Correct statements for the given reaction are:

A. Compound 'B' is aromatic 
B. The completion of above reaction is very slow 
C. 'A' shows tautomerism 
D. The bond lengths C-C in compound B are found to be same 
Choose the correct answer from the options given below:
ClF5 at room temperature is:
The magnetic behavior of Li2O, Na2O2 and KO2, respectively, are

Which of the following compounds would give the following set of qualitative analysis?
• (i) Fehling’s Test: Positive
• (ii) Na fusion extract upon treatment with sodium nitroprusside gives a blood red colour but not

Four gases A, B, C and D have critical temperatures 5.3, 33.2, 126.0 and 154.3K respectively. For their adsorption on fixed amount of charcoal, the correct order is :
The strongest acid from the following is
Which hydride among the following is less stable?