Answer:
[tex]Molecular \: mass \: of \: C _{2}H _{4} O_{2}.2H_{2}O , \\ \\ ⇢ 12 \times 2 + 4 \times 1 + 16 \times 2 + 2(2 \times 1 + 16) \\ \\⇢ 24 + 4 + 32 + 36 \\ \\ ⇢ 96g[/tex]
[tex]\bold\pink{Percentage \: of \: substance \: in \: compound ,} \\ \\ \bold\pink{ ⇢ \frac{mass \: of \: substance}{mass \: of \: compound \times 100}}[/tex]
[tex]\%\:age \: of \: water \: (H_{2}O) = \frac{36}{96} \times 100 \\ \\ ⇢ 0.375 \: \times 100 \\ \\\fbox\red{\: ⇢ 37.5\%\:}[/tex]
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