List of top Chemistry Questions

Find out compound B in the given reaction sequence: \[ {C}_6{H}_6 + {CH}_3X \xrightarrow{{AlCl}_3} A \xrightarrow{{CrO}_3 { in } (CH_3CO)_2O / H_3O^+} B \]

Element with electronic configuration $ 1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^6 4d^{10} 5s^2 5p^3 $ belongs to the following group of the periodic table:

Which of the following will precipitate first when an aqueous solution containing sulphate ions is added?

The probability density plots of 1s and 2s orbitals are given in figure.

The density of dots in a region represents the probability density of finding electrons in the region. On the basis of the above diagram, which of the following statements is incorrect?

Identify A, B and C in the sequence :

Which one is a reaction to prepare CCl₂F₂(freon-12) from CCl₄?

Methylamine reacts with HNO₂ to form?

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are

What will be the concentration of ammonium ions (NH₄⁺) in moles per litre units in a solution having 10 ppm of ammonium ions ?

Choose the correct product formed in the following reaction

The structure of a carborane, $C_2B_5H_7$, is

Identify the major product in the following reaction.

For the reaction
2N₂O₅→4NO₂+0₂
Rate of the reaction is:

The values of van't Hoff factors for NaCl, KCI and K₂SO₄, respectively are

The galvanic cell with the cell reaction
Mg(s) + 2Ag⁺ (0.001M)→ Mg²⁺ (0.65M) + 2Ag(s)
is correctly represented as

Match List I with List II

List I		List II
A.	Carbonyl compounds react with ylide to form alkene.	I.	Cannizzaro Reaction
B.	Ketone reacts with zinc-mercury amalgam in HCl as reducing agent to form alkane.	II.	Clemmensen Reduction
C.	Carbonyl compounds react with basic solution of hydrazine as reducing agent to produce alkane.	III.	Wittig Reaction
D.	Formaldehyde react with NaOH to form methanol.	IV.	Wolf-Kishner Reduction

Choose the correct answer from the options given below:

Which of the following orders are correct for noble gases?
A. Solubility in water He<Ne < Ar<Kr<Xe
B. Boiling points He< Ne <Ar<Kr <Xe
C. Chemical reactivity He > Ne >Ar> Kr > Xe
D. Enthalpy of vaporisation He> Ne > Ar> Kr> Xe
Choose the correct answer from the options given below:

Arachno and nido structure of Boranes have general formula respectively

Deduce the structure of the corresponding alcohol which shows the following reaction
C₆H₁₄0₃ $\stackrel{2HIO_4}{\rightarrow}$ CH₃CHO + CH₃CH₂CHO + HCOOH

The bond enthalpies for C-H, C1-C1, C-C1 and H-Cl are 99, 58, 78 and 103 kcal/mol respectively. What will be the AH for the reaction
CH_4(g) + Cl_2(g) → CH₃Cl_(g) + HCl_(g)

The relative order of stability of conformers of 1,3-dimethylcyclohexane is (equatorial - e, axial-a)

Benzyne bond is formed by the

The phenomenon of existence of two or more compounds possessing the same molecular formula but different properties is referred as ________ .

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: The moving boundary method yields more accurate data on transference number than does the Hittorf method.
Reason R: In moving boundary method, indicator electrolyte has same anion as principal electrolyte and is placed at the bottom due to its higher density.
In the light of the above statements, choose the most appropriate answer from the options given below:

A monochromatic radiation is incident on a solution of 0.05 molar concentration of an absorbing substance. The intensity of the radiation is reduced to one fourth of the initial value after passing through 10 cm length of the solution. Calculate the molar extinction. coefficient of the substance.