$\Rightarrow X:C_6H_4O_4$$O=C-C\equiv C-C=O$ $| |$ $O-C_2H_4-O$$\Rightarrow n_{H_2}=2 mol$
$\Rightarrow X:C_6H_4O_4$$O=C-C\equiv C-C=O$ $| |$ $O-C_2H_4-O$$\Rightarrow n_{H_2}=2 mol$
$\Rightarrow X:C_6H_4O_4$$O=C-C\equiv C-C=O$ $|
|$ $O-C_2H_4-O$$\Rightarrow n_{H_2}=2 mol$