List of top Chemistry Questions asked in JEE Main

C(s)+O2(g)→CO2(g)+400 kJ
C(s)+\(\frac{1}{2}\) O2(g)→CO(s)+100 kJ
When coal of purity 60% is allowed to burn in presence of insufficient oxygen, 60% of carbon is converted into ‘CO’ and the remaining is converted into ‘CO2’. The heat generated when 0.6 kg of coal is burnt is _______.

Compound ‘A’ undergoes following sequence of reactions to give compound ‘B’. The correct structure and chirality of compound ‘B’ is
[where Et is –C2H5]
sequence of reactions to give compound
When ethanol is heated with conc. H2SO4, a gas is produced. The compound formed, when this gas is treated with cold dilute aqueous solution of Baeyer’s reagent, is
Which among the following pairs of the structures will give different products onozonolysis? (Consider the double bonds in the structures are rigid and not delocalized)
The number of stereoisomers formed in a reaction of (±) Ph (C = O) C (OH) (CN) Ph with HCN is_____.
[Where, Ph is – C6H5]
Consider, \(PF_5,BrF_5,PCl_3,SF_6,[ICl_4]^–,ClF_3 and\ IF_5\).
Amongst the above molecule(s)/ion(s), the number of molecule(s)/ion(s) having \(sp^3d^2\) hybridisation is _____.
In a linear tetrapeptide (constituted with different amino acids) – (number of peptide bonds) is _____.
Consider the following sulphur based oxoacids.
\(H_2SO_3,H_2SO_4,H_2S_2O_8 \)and \(H_2S_2O_7\)
Amongst these oxoacids, the number of those with peroxo (O–O) bonds is_____.
Number of lone pairs of electrons in the central atom of SCl2, O3, CIF3 and SF6, respectively, are:
The reaction between X and Y is first order with respect to X and zero order with respect to Y.
reaction between X and Y is first order with respect to X and zero order with respect to Y.
Examine the data of table and calculate ratio of numerical values of M and L. (Nearest integer)
[Fe(CN)6]3– should be an inner orbital complex. Ignoring the pairing energy, the value of crystal field stabilization energy for this complex is (–) _____ Δ0. (Nearest integer)
In bromination of Propyne, with Bromine 1,1,2,2-tetrabromopropane is obtained in 27% yield. The amount of 1,1,2,2-tetrabromopropane obtained from 1 g of Bromine in this reaction is _______ × 10–1 g. (Nearest integer)
(Molar Mass : Bromine = 80 g/mol)
The number of chlorine atoms in bithionol is ______ .
The reaction of zinc with excess of aqueous alkali, evolves hydrogen gas and gives:
In following pairs, the one in which both transition metal ions are colourless is :
Fig,

Consider the above reaction sequence, the product ‘C’ is

Which among the following is the strongest Bronsted base?
Fig.

Considering the above reactions, the compound ‘A’ and compound ‘B’ respectively are :

Consider the above reaction, the compound ‘A’ is :

Fig.
Lithium nitrate and sodium nitrate, when heated separately, respectively, give :
Which among the following pairs has only herbicides?
‘x’ g of molecular oxygen (O2) is mixed with 200 g of neon (Ne). The total pressure of the non-reactive mixture of O2 and Ne in the cylinder is 25 bar. The partial pressure of Ne is 20 bar at the same temperature and volume. The value of ‘x’ is ___.
[Given : Molar mass of O2 = 32 g mol–1 and Molar mass of Ne = 20 g mol–1]
1.80 g of solute A was dissolved in 62.5 cm3 of ethanol and freezing point of the solution was found to be 155.1 K. The molar mass of solute A is ____ g mol–1.
[Given : Freezing point of ethanol is 156.0 K, Density of ethanol is 0.80 g cm–3, Freezing point depression constant of ethanol is 2.00 K kg mol–1]
For a cell, \(Cu(s)|Cu^{2+}(0.001M)||Ag^+(0.01M)|Ag(s)\)
the cell potential is found to be \(0.43 V\) at \(298 K\). The magnitude of standard electrode potential for \(Cu^{2+}/{Cu}\) is ____ \(× 10^{–2}\) V.
[Given: \(E_{Ag^+/Ag^⊖}=0.80\) V and \(\frac {2.303RT}{F}=0.06 V\)]
In neutral or faintly alkaline medium, KMnO4 being a powerful oxidant can oxidize, thiosulphate almost quantitatively, to sulphate. In this reaction overall change in oxidation state of manganese will be