Calculate the relative molecular mass[molecular weight] of 290 ml of a gas A at 17 degrees celsius and 1520 mm pressure which weighs 2.73 gram at S.T.P.

Asked by johncena9384 | 26th Oct, 2018, 04:08: PM

Expert Answer:

Given:
 
P =1520 mm
 
V = 90 ml
 
Weight = 2.73 gm
 
T = 17 °C
 
   = 300 K
 
We have,
 
fraction numerator straight P subscript 1 straight V subscript 1 space over denominator straight T subscript 1 end fraction equals space fraction numerator straight P subscript 2 straight V subscript 2 space over denominator straight T subscript 2 end fraction

fraction numerator 1520 cross times 290 over denominator 290 end fraction space equals space fraction numerator 760 cross times straight V subscript 2 space over denominator 273 end fraction

straight V subscript 2 space equals space 546 space ml

546 space ml space of space gas space at space STP space weighs space 2.73 space straight g.

1000 space ml space of space gas space will space weigh space fraction numerator 1000 cross times 2.73 over denominator 546 end fraction

space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals space 5 space straight g

Vapour space density space equals space fraction numerator Wt space of space 100 space ml space of space gas space at space STP over denominator Wt space of space 1000 space ml space of space straight H subscript 2 space at space STP end fraction

space space space space space space space space space space space space space space space space space space space space space space space space equals fraction numerator 5 over denominator 0.09 end fraction

Vapour space density space equals 55.55

Molecular space weight space equals space 55.55 cross times 2

space space space space space space space space space space space space space space space space space space space space space space space space space space equals space 111.11
 
molecular weight of gas is 111.11

Answered by Varsha | 29th Oct, 2018, 06:15: PM