CBSE
4.0 g molecular PCl5 were heated in a vessel of 6 L volume. At equilibrium state , 50% of PCl5 is dissociated. The equilibrium constant for the reaction is :
0.66 mol L-1
0.33 mol L-1
0.44 mol L-1
0.88 mol L-1
A precipitate of AgCl is formed when equal volumes of the following are mixed :
[Ksp for AgCl = 10-10]
10-4 M AgNO3 and 10-7 M HCl
10-5 M AgNO3 and 10-6 M HCl
10-5 M AgNO3 and 10-4 M HCl
10-6 M AgNO3 and 10-6 M HCl
The pH of blood is :
greater than 10
less than 6
greater than 7 and less than 8
greater than 8 and less than 9
In an exothermic equilibrium ,
A + 3B AB3
all the reactants and products are in gaseous state. The formation of AB3 is favoured at :
low temperature and low pressure
low temperature and high pressure
high temperature and high pressure
high temperature and low pressure
The species among the following, which can act as an acid and a base is :
HS
S
H3O+
Cl-
For a chemical reaction, temperature is raised from 25° C to 35° C. The value of equilibrium constant, Kp is doubled . The heat of reaction (H) for the reaction will be :
13.834 kcal
11.714 kcal
10.726 kcal
4.312 kcal
If in the reaction N2O4 2NO2 , x is that part of N2O4 which dissociates, then the number of molecules at equilibrium will be :
1
3
(1 + X)
(1 + X)2
For the reaction, H2 + I2 2HI, K = 47.6. If the initial number of moles of each reactant and product is 1 mole then at equilibrium
[I2] = [H2] , [I2] > [HI]
[I2] = [H2] , [I2] < [HI]
[I2] < [H2] , [I2] = [HI]
[I2] > [H2] , [I2] = [HI]
If Kb of HCN is 4.0 10-10, then the pH of 2.5 10-1 molar aqueous HCN is
2.0
4.7
5.0
2 x 10-5
H3PO3 is
dibasic acid
basic
tribasic acid
neutral