Answered

A 90.00 g sample of Na, CO *xH, O is heated until all of the water is driven
off, forming 32.28 g of the anhydrous salt, Na, Coz. What is the percent by
mass of H,O in the hydrated compound, Na CO, *xH,O?*

Answer :

ardni313

The percent by  mass of H₂O in the hydrated compound, Na₂CO₃.xH₂O = 64.13%

Further explanation

Given

90 g sample Na₂CO₃.xH₂O

32.28 g Na₂CO₃

Required

The percent by  mass of H₂O

Solution

mass of H₂O = mass of sample - mass of the anhydrous salt, Na₂CO₃

[tex]\tt mass~H_2O=90-32.28=57.72~g[/tex]

The percent by mass :

[tex]\tt \%mass~H_2O=\dfrac{mass~H_2O}{mass~sample}\times 100\%\\\\\%mass~H_2O=\dfrac{57.72}{90}\times 100\%\\\\\%mass~H_2O=64.13\%[/tex]