List of top Questions asked in JEE Main

0.01 M KMnO4 solution was added to 20.0 mL of 0.05 M Mohr’s salt solution through a burette. The initial reading of 50 mL burette is zero. The volume of KMnO4 solution left in burette after the end point is _____ml. [nearest integer]
The compound(s) that is(are) removed as slag during the extraction of copper is : 
  1. \(CaO\) 
  2.  \(FeO\) 
  3.  \(Al _2 O _3\) 
  4.  \(ZnO\)
  5.  \(NiO\) 
    Choose the correct answer from the options given below :
$\dot{ C } l + CH _4 \rightarrow A + B$. $A$ and $B$ in the above atmospheric reaction step are

Consider the above reaction and predict the major product.

Consider the above reaction and predict the major product.

The correct sequential order of the reagents for the given reaction is
In base vs acid titration, at the endpoint methyl orange is present as

For the decomposition of azomethane, CH3N2CH3(g) → CH3CH3(g) + N2(g), a first-order reaction, the variation in partial pressure with time at 600 K is given as
The half-life of the reaction is ______ × 10–5s. [Nearest integer]

In the above reaction product B is:
In the above reaction product B is:
Product B is
Borazine, also known as inorganic benzene, can be prepared by the reaction of 3-equivalents of "$X$" with 6-equivalents of "Y". "X" and "Y", respectively are :
Match List-I with List-II
 

List-I

List-II

(A)Cd(s)+2Ni(OH)3(s)→CdO(s)+2Ni(OH)2(s)+H2O(l)(I)Primary battery
(B)Zn(Hg)+HgO(s)→ZnO(s)+Hg(l)(II)Discharging of secondary battery
(C)2PbSO4(s)+2H2O(l)→Pb(s)+PbO2(s)+2H2SO4(aq)(III)Fuel cell
(D)2H2(g)+O2(g)→2H2O(l)(IV)Charging of
secondary battery

Choose the correct answer from the options given below:

Which of the following has least tendency toliberate $H_2$ from mineral acids?

Match List-I with List-II List-I 

 List-IList-I i
ReactionCatalyst
\(4 NH _3( g )+5 O _2( g ) \rightarrow 4 NO ( g )+6 H _2 O ( g )\)NO(g)
\(N _2( g )+3 H _2( g ) \rightarrow 2 NH _3( g )\)H_2SO_4(l)
\(C _{12} H _{22} O _{11}( aq ) H _2 O (l) \rightarrow \text { (Glucose) }+ C _6 H _{12} O _6 C _6 H _{12} O _6\)Pt(s) 
\( SO _2( g )+ O _2( g ) \rightarrow 2 SO _3( g )\)Fe(s)

Choose the correct answer from the options given below:

The correct stability order of the following diazonium salt is

Among the following structures, which will show the most stable enamine formation? 
(Where Me is –CH3)

Reaction of \(BeCl _2\) with \(LiAlH _4\) gives: Choose the correct answer from options given below : 
  1. \(AlCl _3\)
  2. \(BeH _2\)
  3. \(LiH\)
  4. \(LiCl\)
  5. \(BeAlH _4\)
     
For kinetic study of the reaction of iodide ion with \(H _2 O _2\) at room temperature : 
(A) Always use freshly prepared starch solution 
(B) Always keep the concentration of sodium thiosulphate solution less than that of \(KI\) solution 
(C) Record the time immediately after the appearance of blue colour 
(D) Record the time immediately before the appearance of blue colour 
(E) Always keep the concentration of sodium thiosulphate solution more than that of \(KI\) solution Choose the correct answer from the options given below :
[A] → [B]
Reactant Product
If formation of compound [B] follows the first order of kinetics and after 70 minutes the concentration of [A] was found to be half of its initial concentration. Then the rate constant of the reaction is x × 10–6 s–1. The value of x is _________. (Nearest Integer).
In a linear tetrapeptide (constituted with different amino acids) – (number of peptide bonds) is _____.
The disintegration rate of a certain radioactive sample at any instant is $4250$ disintegrations per minute $10$ minutes later, the rate becomes $2250 $ disintegrations per minute The approximate decay constant is : (Take $\log _{10} 188=0274$ )
Mass numbers of two nuclei are in the ratio of \(4 : 3\). Their nuclear densities will be in the ratio of
Two capacitors, each having capacitance $40 \mu F$ are connected in series The space between one of the capacitors is filled with dielectric material of dielectric constant $K$ such that the equivalence capacitance of the system became $24 \mu F$ The value of $K$ will be :
A wire of resistance $R_1$ is drawn out so that its length is increased by twice of its original length The ratio of new resistance to original resistance is:
In a series LR circuit $X_L=R$ and power factor of the circuit is $P _1$ When capacitor with capacitance $C$ such that $X _{ L }= X _{ C }$ is put in series, the power factor becomes $P _2$ The ratio $\frac{ P _1}{ P _2}$ is
What will be the most suitable combination of three resistors A = 2 Ω, B = 4 Ω, C = 6 Ω so that \((22/3)\) Ω is equivalent resistance of combination?
Resistance of the wire is measured as 2 Ω and 3 Ω at 10°C and 30°C respectively. Temperature co-efficient of resistance of the material of the wire is: