Equilibrium

A weak acid HA has degree of dissociation x. Which option gives the correct expression of (pH - pKa)?

1. ( 1-xx )
2. 0
3. (1+2x)
4. ( x1-x )

Ice and water are placed in a closed container at a pressure of 1 atm and temperature 273.15 K. If pressure of the system is increased 2 times, keeping temperature constant, then identify correct observation from following

1. Liquid phase disappears completely.
2. The amount of ice decreases.
3. The solid phase (ice) disappears completely.
4. Volume of system increases.

Arrange the following in increasing order of solubility product : Ca(OH)2, AgBr, PbS, HgS

1. PbS < HgS < Ca(OH)2 < AgBr
2. HgS < AgBr < PbS < Ca(OH)2
3. HgS < PbS < AgBr < Ca(OH)2
4. Ca(OH)2 < AgBr < HgS < PbS

Ksp for Cr(OH)3 is 1.6 10-30. What is the molar solubility of this salt in water?

1. [5]1.8 10-30
2. 1.8 10-3027
3. [4] 1.6 10-3027
4. [2]1.6 10-30

37.8 g N2O5 was taken in a 1 L reaction vessel and allowed to undergo the following reaction at 500 K 2N2O5(g) 2N2O4(g) + O2(g) The total pressure at equilibrium was found to be 18.65 bar. Then, Kp = 10-2 [nearest integer] Assume N2O5 to behave ideally under these conditions. Given: R = 0.082 bar L mol-1 K-1

For the reaction, H2(g)+I2(g) 2HI(g) Attainment of equilibrium is predicted correctly by :

1. [figure]
2. [figure]
3. [figure]
4. [figure]

Which of the following happens when NH4OH is added gradually to the solution containing 1 M A2+ and 1M B3+ ions? Given : Ksp [A(OH)2] = 9 10-10 and Ksp [B(OH)3] = 27 10-18 at 298 K.

1. A(OH)2 will precipitate before B(OH)3
2. A(OH)2 and B(OH)3 will precipitate together
3. Both A(OH)2 and B(OH)3 do not show precipitation with NH4OH
4. B(OH)3 will precipitate before A(OH)2

If 1 mM solution of ethylamine produces pH=9, then the ionization constant (Kb) of ethylamine is 10-x. The value of x is (nearest integer). [The degree of ionization of ethylamine can be neglected with respect to unity.]

pH of water is 7 at 25 C. If water is heated to 80 C, it's pH will :

1. Decrease
2. Remains the same
3. Increase
4. H+ concentration increases, OH- concentration decreases

Consider the reaction X2Y(g) X2(g) + 12Y2(g) The equation representing correct relationship between the degree of dissociation (x) of X2Y(g) with its equilibrium constant Kp is . Assume x to be very very small.

1. x = [3] KpP
2. x = [3] Kp2P
3. x = [3] 2 Kp2P
4. x = [3] 2KpP