List of top Chemistry Questions

Metals generally melt at very high temperature. Amongst the following, the metal with the highest melting point will be

Using very little soap while washing clothes, does not serve the purpose of cleaning of clothes, because:

In the following structures, which one is having staggered conformation with maximum dihedral angle?

The number of bridged oxygen atoms present in compound B formed from the following reactions is

\(PB(NO_3)^2→(673 K)→A+PBO+O_2A→(Dimerise)B.\)

Solute A associates in water. When 0.7 g of solute A is dissolved in 42.0 gof water, it depresses the freezing point by 0.2°C. The percentage association of solute A in water is :

[Given : Molar mass of A = 93 g mol^–1. Molal depression constant of water is 1.86 K kg mol^–1.]

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Polluted water may have a value of BOD of the order of 17 ppm.

Reason R: BOD is a measure of oxygen required to oxidise both the bio-degradable and non-biodegradable organic material in water.

In the light of the above statements, choose the most appropriate answer from the options given below.

The correct order of electron gain enthalpies of Cl, F, Te and Po is

Which one of the following is an example of artificial sweetner?

Choose the correct answer :

1. The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is

[Given The threshold frequency of platinum is 1.3 × 10¹⁵ s^–1 and h = 6.6 × 10^–34 Js.]

The Ksp for bismuth sulphide (Bi₂S₃) is 1.08 × 10^–73. The solubility of Bi₂S₃ in mol L^–1 at 298 K is

The correct order of bond orders of \(C_2^{2-}, N_2^{2-}, O_2^{2-}\) is, respectively

The major product in the reaction is:

The major product in the reaction with product2-Methyl prop-1-ene

Octahedral complexes of copper(II) undergo structural distortion (Jahn-Teller). Which one of the given copper(II) complexes will show the maximum structural distortion?
(en – ethylenediamine;H₂N−CH₂−CH₂−NH₂)

Which among the following represents reagent ‘A’?

Portland cement contains ‘X’ to enhance the setting time. What is ‘X’?

A compound ‘X’ is a weak acid and it exhibits colour change at pH close to the equivalence point during neutralization of NaOH with CH₃COOH. Compound ‘X’ exists in ionized from in basic medium. The compound ‘X’ is

Given below are two statements.
Statement I: The compound

(A) is optically active.
Statement II:

is a mirror image of the above compound A.
In the light of the above statement, choose the most appropriate answer from the options given below.

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

Correct structure of γ-methylcyclohexane carbaldehyde is

Which of the following 3d-metal ion will give the lowest enthalpy of hydration (Δ_hydH) when dissolved in water?

Which of the following compounds is an example of hypnotic drug?

Consider the following reaction sequence:

The product ‘B’ is:

Which of the following is not a natural polymer?

In liquation process used for tin (Sn), the metal

Given below are two statements.
Statement-I: Stannane is an example of a molecular hydride.
Statement-II: Stannane is a planar molecule
In the light of the above statement, choose the most appropriate answer from the options given below.