JEE Main entrance exam Question Bank Solutions

The decreasing order of electrical conductivity of the following aqueous solutions is:

1. 0.1 M Formic acid,
2. 0.1 M Acetic acid,
3. 0.1 M Benzoic acid.

The reaction of benzene with CO and HCl in the presence of anhydrous AlCl₃ gives ______.

The number of π-bonds present in Marshall's acid is ______.

Reagent used to convert allyl alcohol to acrolein is ______.

Which of the following is a correct statement?

The conditions given below are in the context of observing Tyndall effect in colloidal solutions:

1. The diameter of the colloidal particles is comparable to the wavelength of light used.
2. The diameter of the colloidal particles is much smaller than the wavelength of light used.
3. The diameter of the colloidal particles is much larger than the wavelength of light used.
4. The refractive indices of the dispersed phase and the dispersion medium are comparable.
5. The dispersed phase has a very different refractive index from the dispersion medium.

Choose the most appropriate conditions from the options given below:

Given below are two statements:

Statements I: The limiting molar conductivity of KCl (strong electrolyte) is higher compared to that of CH₃COOH (weak electrolyte).

Statement II: Molar conductivity decreases with decrease in concentration of electrolyte.
In the light of the above statements, choose the most appropriate answer from the options given below:

Coagulation value of the electrolytes AlCl₃ and NaCl for As₂S₃ sol are 0.093 and 52 respectively. The No. of times AlCl₃ has greater coagulating power than NaCl is ______.

The solubility of Co₂[Fe(CN)₆] in water at 25°C from the following data:

Conductivity of saturated solution of Co₂[Fe(CN)₆] = 2.06 × 10⁻⁶ ohm⁻¹ cm⁻¹ and that of water = 4.1 × 10⁻⁷ ohm⁻¹ cm⁻¹. The ionic molar conductivities of Co²⁺ and [Fe(CN)₆]⁴⁻ are 86 and 444 ohm⁻¹ cm² mol⁻¹ respectively, is ______ × 10⁻⁶ mol/L.

In order to cause coagulation of 100 ml Arsenious sulphide sol 111.7 mg of 2 M NaCl solution is used, the coagulation value of NaCl will be ______.

6.84 g Al₂(SO₄)₃ is needed to coagulate 2.5 L of As₂S₃ sol completely in 2.0 hrs. The coagulation value of Al₂ (SO₄)₃ is ______.

Benzene on ozonolysis followed by hydrolysis gives ______.

The variation of molar conductivity with concentration of an electrolyte (X) m aqueous solution is shown in the given figure.

The electrolyte X is ______.

Lyophilic sols are more stable than lyophobic sols because ______.

Heating white phosphorus with conc. NaOH solution gives mainly ______.

Assertion: Nitrogen and oxygen are the main components in the atmosphere but these do not react to form oxides of nitrogen.

Reason: The reaction between nitrogen and oxygen requires high temperature.

At 25°C and 1 atm pressure, the enthalpies of combustion are as given below:

The enthalpy of the formation of ethane is:

Which of the following statements is correct?

(a) The electronic configuration of Cr is (Ar) 3d⁵ 4s¹.

(b) The magnetic quantum number may have a negative value.

(c) In the ground state of an atom, the orbitals are filled in order of their increasing energies.

(d) The total number of nodes are given by n − 2.

Choose the most appropriate answer from the options given below:

Two isomers 'A' and 'B' with molecular formula C₄H₈ give different products on oxidation with KMnO₄ in acidic medium. Isomer 'A' on reaction with KMnO₄/H⁺ results in the effervescence of gas and gives ketone. The compound 'A' is:

4.5 g of compound A (MW = 90) was used to make 250 mL of its aqueous solution. The molarity of the solution in M is x × 10⁻¹. The value of x is ______. (Rounded-off to the nearest integer)