Class 12th

Catalyst A reduces the activation energy for a reaction by 10 kJ mol^-1 at 300K. The ratio of rate constants, $\frac{k_T,Catalysed}{k_T,Uncatalysed}is{e}^x.$  The value of x is_________. (nearest integer)

[Assume that the pre-exponential factor is same in both the cases. Given R = 8.31 JK^-1 mol^-1]

A sample of an ideal gas is taken through the cyclic process ABCA as shown in figure. It absorbs, 40 J of heat during the part AB, no heat during BC and rejects 60 J of heat during CA. A work of 50 J is done on the during the part BC. The internal energy of the gas at A is 1560 J. The work done by the gas during the part CA is:

Cu(s) + Sn²⁺(0.001M) ® Cu²⁺ (0.01M) + Sn(s)

The Gibbs free energy change for the above reaction at 298 K is x * 10^-1 KJmol^-1. The value of x is __________. (nearest integer)

[Given : $E_{C{u}^{2+}/Cu}^{\Theta }$ 0.34V; $E_{S{n}^{2+}/Sn}^{\Theta }$ =96500 Cmol^-1] 

40% of HI undergoes decomposition to H₂ and I₂ at 300K. $\Delta G^{\Theta }$ for this decomposition reaction at one atmosphere pressure is_____________J mol^-1 (nearest integer)

(Use R = 8.31 JK^-1 mol^-1; log 2= 0.3010, In 10 = 2.3, log 3 = 0.477)

The osmotic pressure exerted by a solution prepared by dissolving 2.0g of protein of molar mass 60 kg mol^-1 in 200 mL of water at 27°C is_______Pa. (nearest integer)

(Use R = 0.083 L bar mol^-1 K^-1)

A fish swimming in water body when taken out from the water body is covered with a film of water of weight 36g. When it is subjected to cooking at 100°C, then the internal energy for vaporization in kJ mol^-1 is_____________. (nearest integer)

[Assume steam to be an ideal gas. Given  ${\Delta }_{vap}{H}^{\Theta }$ for water at 373K and 1 bar is 41.1 kJ mol^-1; R = 8.31 JK^-1mol^-1]

Which statement is not true with respect to nitrate ion test?

Amongst SF₄, XeF₄, CF₄ and H₂O, the number of species with two lone pairs of electrons is___________.

In a solid AB, A atoms are in ccp arrangement and B atoms occupy all octahedral sites. If two atoms from the opposite face are removed, then the resultant stoichiometry of the compound is A_xB_y. The value of x is ___________(nearest integer)

A chemical which stimulates the secretion of pepsin is