Answer:
The volume of the flask is<u> 20.245 litres .</u>
Explanation:
We are given with following information-
-------- 1
where R =
Molar mass of 
The given chemical equation is -
--------- 2
Now , calculation -
Mass of
formed = 118g
Molar mass of
= 
Mole = 
Therefore , moles of
formed = 
From equation 2 , we get to know that ,
2mole
formed from 5 mole 
Therefore ,
mole
formed from
mole 
Moles of
used =
R= 
Pressure (P)= 1.85atm
Temperature (T)= 322K
Moles of
(n)=
moles
Applying the formula above in 1 equation , that is
PV = nRT
putting the given values -

V = 20.245 litres.
Hence , the volume of the flask is <u>20.245 litres . </u>