IIT-JEE-Chemistry-Final Revision Set No.56

1. At constant temperature, the equilibrium constant (KP) for the decomposition reaction N2 O4 2NO2 is expressed by KP=4x² P/(1-x²), where P= pressure,

x = extent of decomposition. Which one of the following statements is true:
(a) KP increases with increase of P
(b) KP increases with increase of x
(c) KP increases with decrease of x
(d) KP remains constant with change in P and x

2. If 'I' is the intensity of absorbed light and ‘C’ is the concentration of AB for the photochemical process AB+hv → AB* , the rate of formation of AB* is directly proportional to :
(a) C
(b) I
(c) I2
(d) C.I

3. Saturated solution of KNO3 is used to make ‘salt-bridge’ because :
(a) Velocity of K+ is greater than that of NO3-
(b) Velocity of NO3-is greater than that of K+
(c) Velocities of both K+and NO3-are nearly the same
(d) KNO3 is highly soluble in water.

4. The reaction, 3ClO(aq)- → ClO3(aq)- + 2Cl(aq)- is an example of :
(a) Oxidation reaction
(b) Reduction reaction
(c) Disproportionate reaction
(d) Decomposition reaction

5. The number of s-s bonds in sulphur trioxide timer (S3O9) is :
(a) Three
(b) Two
(c) One
(d) Zero

source: 2001 Jee Screening