If this is just a general question it seems to vary from about 4.5g to 5g. Is there more data to the question?
Answer:
I
Explanation:
The complete question can be seen in the image attached.
We need to understand what is actually going on here. In the first step that yields product A, the sodamide in liquid ammonia attacks the alkyne and abstracts the acidic hydrogen of the alkyne. The second step is a nucleophilic attack of the C6H5C≡C^- on the alkyl halide to yield product B (C6H5C≡C-CH3CH2).
Partial reduction of B using the Lindlar catalyst leads to syn addition of hydrogen to yield structure I as the product C.
Calculate the mass of water used
that is
100-22.2=77.8g convert into Kg = 77.8/1000=0.0778Kg of water
then calculate the moles of HCOOH used
that is 22.2g/molar mass of HCOOH(1+12+16+16+1)=46
therefore the moles of HCOOH=22.2/46=0.48moles
the mole of water= 77.8/18(molar mass of water= 4.32moles
the molarity of HCOOH = 0.48mol/0.0778kg=6.17M
The mole ratio= moles of HCOOH divided by total moles
the total moles= 0.48+4.32=4.8moles
therefore the mole ratio= 0.48/4.8moles=0.1(the moles fraction of HCOOH)