Chemistry

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: A reaction can have zero activation energy.
Reason R: The minimum extra amount of energy absorbed by reactant molecules so that their energy becomes equal to threshold value, is called activation energy.

In the light of the above statements, choose the correct answer from the options given below:

For a certain reaction, the rate = k[A]²[B]. When the initial concentration of A is tripled keeping concentration of B constant, the initial rate would

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: In equation ΔG = -nFEcell, value of ΔG depends on n.
Reason R: Ecell is an intensive property and ΔG is an extensive property.

In the light of the above statements, choose the correct answer from the options given below:

The conductivity of centimolar solution of KCl at 25°C is 0.0210 ohm^-1 cm^-1 and the resistance of the cell containing the solution at 25°C is 60 ohm. The value of cell constant is:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: Helium is used to dilute oxygen in diving apparatus.
Reason R: Helium has high solubility in O₂.

In the light of the above statements, choose the correct answer from the options given below:

A compound is formed by two elements A and B. The element B forms cubic close packed structure and atoms of A occupy 1/3 of tetrahedral voids. If the formula of the compound is A?B?, then the value of x + y is in option

Weight (g) of two moles of the organic compound, which is obtained by heating sodium ethanoate with sodium hydroxide in presence of calcium oxide is:

The number of σ bonds, π bonds and lone pair of electrons in pyridine, respectively are

In Lassaigne's extract of an organic compound, both nitrogen and sulphur are present, which gives blood red colour with Fe³⁺ due to the formation of

Match List-I with List-II
List-I: A. Coke, B. Diamond, C. Fullerene, D. Graphite
List-II: I. Carbon atoms are sp³ hybridised, II. Used as a dry lubricant, III. Used as a reducing agent, IV. Cage like molecules

Choose the correct answer from the options given below: