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[MAAK]

can u tell me how did they get the answer for MCQ Q 20 N 21 MAY/JUNE 09 CHEMISTRY PAPER 1

 

[SalmanPakRocks]

LINK

 

[leosco1995]

20) An alkali is being added to an acid, so the pH would increase meaning A and B are definitely out of the question. But that doesn't mean the solution will always have a pH of 7 so don't be swayed by that. 'until no further change of pH took place' suggests that the pH will probably increase to 12. So the answer would be D.
21) Nicken is a catalyst used in hydrogenation of alkenes. A catalyst lowers the activation energy, so the answer is B.