Answers

2015-05-18T17:31:22+05:30
molecular weight of ammonia = 17 ( 14 +3)
17g of ammonia contains 6.023×10∧23
then 4.25g contains 6.023×10∧23 / 17 ×4.25 = 1.5×10∧23
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2015-05-18T17:31:47+05:30
17g of NH3 have atom=6.022x10^23
1g...........................=6.022x10^23
                                   17
4.25...........................= 6.022x10^23    x 4.25=1.50x10^23 atom
                                         17
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