JEE Main entrance exam Question Bank Solutions for Chemistry (JEE Main)

The correct order of the spin-only magnetic moment of metal ions in the following low spin complexes,

\[\ce{[V(CN)6]^{4-}, [Fe(CN)6]^{4-}, [Ru(NH3)6]^{3+} and [Cr(NH3)6]^2}\] is:

The major Product of the following reaction is:

A drop of solution (volume 0.05 ml) contains 3.0 × 10^-6 mole of H⁺. If the rate constant of disappearance of H⁺ is 1.0 × 10⁷ mole l^-1s^-1. It would take for H⁺ in drop to disappear in ______ × 10^-9s.

For a chemical reaction starting with some initial concentration of reactant A_t as a function of time (t) is given by the equation,

`1/("A"_"t"^4) = 2 + 1.5 xx 10^-3` t

The rate of disappearance of [A] is ____ × 10^-2 M/sec when [A] = 2 M.

[Given: [A_t] in M and t in sec.]
[Express your answer in terms of 10^-2 M /s]
[Round off your answer if required]

A strong current of trivalent gaseous boron passed through a silicon crystal decreases the density of the crystal due to part replacement of silicon by boron and due to interstitial vacancies created by missing Si atoms. In one such experiment, one gram of silicon is taken and the boron atoms are found to be 1000 ppm by weight, when the density of the Si crystal decreases by 12%. The percentage of missing vacancies due to silicon, which are filled up by boron atoms will be ____ g. [Given · Atomic wt. Si= 30, B = 11]

Consider an isothermal cylinder and massless piston assembly in which ideal gas is filled. Cross-sectional area of the cylinder = 1 m². Three masses m₁, m₂ and m₃ are kept on the piston. When m₁ is removed, the piston moves upto point A. When m₁ and m₂ both are removed piston moves upto point B and when m₁, m₂ and m₃ all three are removed, piston moves upto point C. The work done by the gas is ______ J, when piston moves from point B to point C.

[Given : m₁ = 2 × 10⁴ kg, m₂ = 3 × 10⁴ kg, g = 10 m/s²]

The density of solid Argon is 1.6 ml at - 233°C. If the Argon atom is assumed to be sphere of radius 1.5 × 10^-8 cm, then the ______ % of solid Argon is apparently occupied.

[Take : N_A = 6 × 10²³, Atomic mass of Ar = 40]

On small scale, boron is best isolated by reducing boron trioxide with ______.

A given solution of H₂O₂ is 30 volumes. Its concentration in terms of molarity is ______.

Glycinato ligand is ______.

The composition of a sample of wustite is Fe_0.93O_1.0· The iron is present in the form of Fe(III) is ______%.

A sample of Ferrous sulphide reacts with dil. H₂SO₄ to from H₂S which contains 9% hydrogen by volume. The percentage of fee in the sample, is ______.

The molarity of the solution prepared by dissolving 6.3 g of oxalic acid (H₂C₂O₄ · 2 H₂O) in 250 mL of water in mol L^-1 is x × 10^-2. The value of x is ______. (Nearest integer)

[Atomic mass: H : 1.0, C : 12.0, O : 16.0]

The mole fraction of a solute in a 100 molal aqueous solution is ______ × 10^-2. (Round off to the Nearest Integer).

[Given :Atomic masses : H : 1.0 u, O : 16.0 u]

A flask contains a mixture of compounds A and B. Both compounds decompose by first-order kinetics. The half-lives for A and B are 300 s and 180 s, respectively. If the concentrations of A and B are equal initially, the time required for the concentration of A to be four times that of B (in s) is ______. (Use ln 2 = 0.693)

Match List - I with List - II.

Choose the correct answer from the options given below:

Calamine and Malachite, respectively, are the ores of ______.

The ore that contains both iron and copper is ______.

4 ml of pure A (d = 2.45 gm/ml) was added to 46 ml of B (d = `25.1/23` gm/ml), the molarity of a solution of A in B will be ______, if the density of the final solution is 1.8 gm/ml.

Given: Molar mass of A = 98, Molar mass of B = 46

The group number, number of valence electrons, and valency of an element with atomic number 15, respectively, are ______.