631. In which of the following equilibria will Kc and Kp have the same value ?
A. PCI5 = PCI3 + Cl2
B. N2 + 3H2 = 2NH
C. 2CO + O2 = CO2
D. N2 + O2 = 2NO

632. Which of following is not a base______________?
A. KOH
B. NH3
C. PH3
D. BF3

633. Which set of solutes will form a buffer when dissolved in water to make 1 litter of solution ?
A. 0.0002M HCI
B. 0.2 mole of NaCI with 0.2 mole of HNO3
C. 0.4 mole of CH3COOH with 0.4 mole of NaOH
D. 0.4 mole of NH3 with 0.2 mole of HCI

634. Chemical equilibrium state is_______________?
A. dynamic state
B. static state
C. free state
D. unidirectional state

635. At start of reaction the concentration of reactants is_______________?
A. high
B. low
C. according to Kc
D. constant

636. In case of gases Kc is replaced by_______________?
A. Ka
B. Kb
C. Kp
D. K

637. When the value of Kc is very small then_______________________?
A. reaction is at start
B. product conc. Is maximum
C. reactant conc. Is minimum
D. reaction is completed

638. Idea of pH and pOH was put forward by________________?
A. Gibbs
B. Einstein
C. Sorenson
D. Chadwick

639. Ka<10-3 means______________?
A. Very strong base
B. Very weak acid
C. Very strong acid
D. Very strong salt

640. Which of the following is a macro nutrient ?
A. boron
B. iron
C. copper
D. carbon