+2 chemistry - Important one mark questions - Fourth Set - Part 2

           Tamil Nadu +2 chemistry - Important  one mark questions

7. Which of the following is used as neutron absorber in nuclear reactors?

(a) Water            (b) Deuterium              (c) Uranium        (d) Cadmium

 8. The number of chloride ions present per unit cell of Cesium chloride

(a)     6                  (b)     8                  (c)      1                  (d)     4

 9. When liquid boils, there is

(a) An increase in entropy                                (b) a decrease in entropy

(c) An increase in heat of vapourisation            (d) an increase in free energy   

 10. State of chemical equilibrium is

(a) Dynamic           (b) stationary               (c)both a & b                   (d)none

11. Heat evolved or absorbed in a process at constant T and P is represented as

(a) ∆E                    (b) ∆S                              (c) ∆G                    (d) ∆H

12. Initial temperature of a machine is 383 K. After doing work, the decrease in its temperature is 85 K. Percentage of efficiency of the machine is

(a) 4.5                     (b) 100                            (c) 77.8                  (d) 22.2

13. t_1/2 of first order reaction is 10 minutes. Its rate constant is -------- min^-1

(a) 693                   (b) 6.93                           (c) 0.00693             (d) 0.0693

14. In 1 lit vessel, 2 moles of NH₃ taken and heated. At equilibrium, one mole of NH₃ remains, value of K_c is

(a)  27/8               (b) 27/16            (c) 27/4            (d) 27/2