List of top Chemistry Questions asked in JEE Main

A gaseous mixture of two substances A and B, under a total pressure of 0.8 atm is in equilibrium with an ideal liquid solution. The mole fraction of substance A is 0.5 in the vapour phase and 0.2 in the liquid phase. The vapour pressure of pure liquid A is ______ atm. (Nearest integer)
The standard free energy change \((ΔG°)\) for \(50%\) dissociation of \(N_2O_4\) into \(NO_2\) at \(27°C\) and 1 atm pressure is \(x\ J mol^{–1}\). The value of \(x\) is _____. (Nearest Integer)
[Given : \(R = 8.31\ JK^{–1} mol^{–1}\), \(log\ 1.33 = 0.1239\), \(ln\ 10 = 2.3\)]

The number of statement(s) correct from the following for Copper (at. no. 29) is/are ______.

  1. Cu(II) complexes are always paramagnetic
  2. Cu(I) complexes are generally colourless
  3. Cu(I) is easily oxidized
  4. In Fehling solution, the active reagent has Cu(I)
If O2 gas is bubbled through water at 303 K, the number of millimoles of O2 gas that dissolve in 1 litre of water is_______. (Nearest integer)
(Given : Henry’s Law constant for O2 at 303 K is 46.82 k bar and partial pressure of O2 = 0.920 bar)
(Assume solubility of O2 in water is too small, nearly negligible)
Which of the following is structure of a separating funnel?
Match List-I with List-II
 List I List II
A.Lyophilic colloidiLiquid-liquid colloid
B.EmulsioniiProtective colloid
C.Positively chargediii\(FeCl_3 + NaOH\)
D.Negatively chargediv\(FeCl_3 + hot\; water\)

Choose the correct answer from the options given below :

The number of radial and angular nodes in 4d orbital are, respectively
‘A’ and ‘B’ respectively are: \(A\xrightarrow[(2)Zn-H_2O]{(1)O_3}\)
\(Ethane-1, 2-dicarbaldehyde + Glyoxal/Oxaldehyde\)
\(B \xrightarrow[(2)Zn-H_2O]{(1)O_3}   5 - oxohexanal\)
Match List-I with List-II.
 List I List II
A.Concentration ofiAniline
B. Leaching of aluminaiiNaOH
C.Froth stabilizeriii\(SO_2\)
D.Blister copperivNaCN

Choose the correct answer from the options given below.

Which of the following elements is considered as a metalloid?
The role of depressants in ‘Froth Floation method’ is to
Addition of \(H_2SO_4\) to \(BaO_2\) produces:
\(BeCl_2\) reacts with \(LiAlH_4\) to give:
Heating white phosphorus with conc. \(NaOH\) solution gives mainly:
Given below are two Statements:
Statement I: Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide.
Statement II: Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc.
In the light of the above statements, choose the most appropriate answer from the options given below.
The major product of the following reaction is:
 Chemical Reaction With No2FI
Match List-I with List-II
List-I
(A) Spontaneous process
(B) Process with \(ΔP = 0\), \(ΔT = 0\)
(C) \(ΔH_{reaction}\)
(D) Exothermic Process
List-II
(I) \(ΔH < 0\)
(II) \(ΔG_{T,P} < 0\)
(III) Isothermal and isobaric process
(IV) [Bond energies of molecules in reactants] – [Bond energies of product molecules]
Choose the correct answer from the options given below :
Match List-I with List-II
 List i List II
A.
Ch3(CH2)15
iDishwashing power
B.
CH3-(CH2)11
iiToothpaste
C.\(C_{17}H_{35}COO^–Na^++Na_2CO_3+Rosinate\)iiiLaundry soap
D.\(CH_3(CH_2)_{16}COO(CH_2CH_2O)CH_2CH_2OH\)ivHair conditional
Choose the correct answer from the options given below:
Which of the following will have maximum stabilization due to crystal field?
Based upon VSEPR theory, match the shape (geometry) of the molecules in List-I with the molecules in
List-II and select the most appropriate option.
  List-I                            List-II
(Shape)                    (Molecules)
(A) T-shaped             (I) XeF4
(B) Trigonal planar     (II) SF4
(C) Square planar       (III) CIF3
(D) See-saw                (IV) BF3
Match List-I with List-II
 (Polymer)  (Used in)
A.BakeliteiRadio and television cabinets
B.GlyptaliiElectrical switches
C.PVCiiiPaints and Lacqures
D.PolystyreneivWater pipes

Choose the correct answer from the options given below:

The oxide which contains an odd electron at the nitrogen atom is
The most common oxidation state of Lanthanoid elements is +3. Which of the following is likely to deviate easily from +3 oxidation state?
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The ionic radii of \(O^{2–}\) and \(Mg^{2+}\) are same.
Reason (R) : Both \(O^{2–}\) and \(Mg^{2+}\) are isoelectronic species.
In the light of the above statements, choose the correct answer from the options given below.
Match List I with List II
List I EnzymeList II Conversion of
AInvertaseIStarch into maltose
BZymaseIIMaltose into glucose
CDiastaseIIIGlucose into ethanol
DMaltaseIVCane sugar into glucose

Choose the most appropriate answer from the options given below: