The electrode potential of M²⁺/M of 3d-series elements shows positive value for :

Which of the following reagent is used for the following reaction ?

$$ \mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_3 \stackrel{?}{\longrightarrow} \mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CHO} $$

Which of the following are isostructural pairs ?

A. $$SO_4^{2 - }$$ and $$CrO_4^{2 - }$$

B. SiCl₄, and TiCl₄

C. NH₃ and NO₃^-

D. BCl₃ and BrCl₃

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is :

Out of the following, which type of interaction is reponsible for the stabilisation of $$\alpha $$-helix structure of proteins ?

Which of the following compound gives pink colour on reaction with phthalic anhydride in conc. H₂SO₄ followed by treatment with NaOH ?

Given below are two statements :

Statement I : Colourless cupric metaborate is reduced to cuprous metaborate in a luminous flame.

Statement II : Cuprous metaborate is obtained by heating boric anhydride and copper sulphate in a non-luminous flame.

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

In the following reaction the reason why meta-nitro product also formed is :

What is the major product formed by HI on reaction with

'A' and 'B' in the following reactions are :

Identify products A and B.

What is the final product (major) 'A' in the given reaction ?

The product formed in the first step of the reaction of


with excess $$\mathrm{Mg/Et_2O}$$ ($$\mathrm{Et=C_2H_5}$$) is

Number of amphoteric compounds among the following is ________.
(A) BeO
(B) BaO
(C) Be(OH)₂
(D) Sr(OH)₂

The stepwise formation of $${\left[ {Cu{{\left( {N{H_3}} \right)}_4}} \right]^{2 + }}$$ is given below:


The value of stability constants K₁, K₂, K₃ and K₄ are 10⁴, 1.58 x 10³, 5 x 10² and 10² respectively.
The overall equilibrium constants for dissociation of $${\left[ {Cu{{\left( {N{H_3}} \right)}_4}} \right]^{2 + }}$$ is x $$ \times $$ 10^-12.
The value of x is ________. (Rounded off to the nearest integer)

A proton and a Li³⁺ nucleus are accelerated by the same potential. If $$\lambda _{Li}$$ and $$\lambda _p$$ denote the de Broglie wavelengths of Li³⁺ and proton respectively, then the value of $${{{\lambda _{Li}}} \over {{\lambda _p}}}$$ is x $$ \times $$ 10^-1.
The value of x is ______. (Rounded off to the nearest integer)
[Mass of Li³⁺ = 8.3 mass of proton]

At 1990 K and 1 atm pressure, there are equal number of Cl₂, molecules and Cl atoms in the reaction mixture. The value of K_p for the reaction Cl_{2 (g)} $$ \rightleftharpoons $$ 2Cl_(g) under the above conditions is x $$ \times $$ 10^-1.
The value of x is _______. (Rounded off to the nearest integer)

When 9.45 g of CICH₂COOH is added to 500 mL of water, its freezing point drops by 0.5°C. The dissociation constant of CICH₂COOH is x $$ \times $$ 10^-3.
The value of x is ________. (Rounded off to the nearest integer)
[K_f(H20) = 1.86 K kg mol^-1]

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 $$ \times $$ 10^-1.
The value of x is _______. (Rounded off to the nearest integer)

The reaction of sulphur in alkaline medium is given below:


The values of 'a' is _______. (Integer answer)

For the reaction A_(g) $$ \to $$ B_(g) the value of the equilibrium constant at 300 K and 1 atm is equal to 100.0. The value of $$\Delta $$_rG for the reaction at 300 K and 1 atm in J mol^-1 is – xR, where x is _______. (Rounded off to the nearest integer)
[R = 8.31 J mol^–1K^-1 and ln 10 = 2.3)

Gaseous cyclobutene isomerises to butadiene in a first order process which has a 'k' value of 3.3 $$ \times $$ 10^-4 s^-1 at 153°C. The time in minutes it takes for the isomerization to proceed 40% to completion at this temperature is ______.
(Rounded off to the nearest integer)