List of top Chemistry Questions asked in JEE Main

Find out difference in oxidation state of Xe in completely Hydrolysed form of XeF4 and XeF6
2 gm of x is present in 1 mole of H2O.Find the mass % of x
\([Co(NH_3)_6]^{3+} \text{is} \) ________\(\text{hybridised and}\)________
While performing a thermodynamics experiment, a student made the following observations, 

$ HCl + NaOH \rightarrow NaCl + H _2 O$

$ \Delta H =-573 \,kJ \,mol ^{-1}$ 

$ CH _3 COOH + NaOH \rightarrow CH_3COONa + H _2 O$ 

$ \Delta H =-553 \,kJ\, mol ^{-1} $ 

The enthalpy of ionization of $CH _3 COOH$ as calculated by the student is _____ $kJ \,mol ^{-1}$ (nearest integer)

25% of 250g sugar solution & 40% of 500g sugar solution are mixed then find out the mass percentage in the solution.
How many of the following are bent in shape? 
SO2, O3, I3-, N3-

Find the spin magnetic moment ratio for complexes \([Cr(Cn)_{6}]^{-3}\) & \([Cr(H_{2}O)_{6}]^{+3}\)

By weight, 23% NaCl and 19.5% MgCl2 are present in salt water. The degree of dissociation of both salts is 100%. Find the average boiling point of salt water (inºC). (Kb = 0.52 K kg mol–1) (Nearest integer)

NH3, NO, N2, F2, CO, CO2, H2O, and XeF4. Fill the number of above molecules having only two lone pair of electrons.
Ksp of BaSO4 is 8 × 10–11. If the solubility in presence of 0.1 M CaSO4 is?

Glucose is added in 100 gm of water. Lowering in vapor pressure is 0.2 mm Hg. Vapour pressure of pure water is 54.2 mm Hg. Then the weight of glucose is?

A binary compound has Y-atoms forming FCC unit cell and another type of X-atoms occupying \(\frac{1}{3}\)rd of tetrahedral voids. Find out the molecular formula of the compound

 

How many electrons are gained by MnOΘ4 in strongly alkaline medium?
The pressure value of a gas is 930.2 mm Hg. The volume is then reduced to 40% of its initial value at a constant temperature. Then what is the final pressure (in mmHg)
Radius of the 2nd orbit of He+ is r0. Radius of the 4th orbit of Be3+ is xr0. Find x.
Oxidation state of Cr in chromyl chloride is:
Lowering of vapour pressure of 30% of aqueous solution of glucose. (in mmHg) 
Given: PH2O = 760 mm of Hg
How many of the following statements are correct:
Number of P-O-P bonds in H3PO4, P4O10, (HPO3)3

Some amount of urea is added to 1000 gm of H2O due to which vapor pressure decreases by 25% of the original vapor pressure. Find out the mass of urea added (Round off to two decimal places)

In which form does \(BeCl_{2}\) exist in the solid state, vapor state and high temperature?
Match the terms in Column-I with their description in Column-II:
Column-I Column-II
PN2O5 (i)N–N bond
QN2O(ii)N–O–N bond
RN2O4 (iii)N=N / N≡N bond
SNO2(iv)N=O bond
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Radius of H+ is 1.5 × 10–3 pm
Reason (R) : H+ cannot exist independently
In the light of the above statements, write the detailed answer:

Which of the following slows down the process of setting of the cement? 

When 2 gm magnesium reasts with excess of HCl and H2 gas is produced then the volume of H2 gas produced is ____ × 10–2 liter at STP. (Nearest Integer)