324g of 20% by mass of Ba(OH)2 solution

Asked by arunparewa2000 | 27th Oct, 2021, 06:59: PM

Expert Answer:

The mass of Ba(OH)2 is 342 g.
 
The molar mass of Ba(OH)is 171 gm
 
Hence, 1 mole of Ba(OH)2 is the molar mass of Ba(OH)2 is 171 gm
 
So, for 342 g. wil be x
 
 
straight x equals 342 over 171 equals space 2 space moles
We know 100% by mass is 2moles hence 20% will be x.
 
straight x space equals space fraction numerator 20 cross times 2 over denominator 100 end fraction space 0.4 space moles
 
The space total space moles space of space Ba left parenthesis OH right parenthesis subscript 2 space equals space 2 space cross times space 0.4 space equals space 0.8
 
As given the molarity of HNO3 is 2M, So, the total moles=
 
 straight M space equals space fraction numerator straight n cross times 1000 over denominator straight V end fraction

straight n space equals space fraction numerator 2 cross times 1200 over denominator 1000 end fraction

straight n space equals space 2.4 space moles
 
 
Total acidic excess moles = 2.4 - 0.8 = 1.6
 
The total volume of Ba(OH)2 is straight d space equals space straight w over straight v
straight v space equals space fraction numerator 342 over denominator 0.57 end fraction space equals space 600 ml
 
The volume of HNO3 is 1200ml
 
Hence the total volume of Ba(OH)2 = 1200+600 =1800 ml
 
straight M space equals fraction numerator straight n cross times 1000 over denominator straight V end fraction
straight M space equals space fraction numerator 1.6 cross times 1000 over denominator 1800 end fraction
straight M space equals space 0.88 straight M
 

Answered by Ramandeep | 28th Oct, 2021, 02:50: PM