26.8 g of Na_2SO_4.xH_2O gave 12.6 g of water on heating. Determine the value of x in the compound using mole concept.

26.8 g of Na_2SO_4.xH_2O gave 12.6 g of water on heating. Determine th

1.	26.8 g of Na_2SO_4.xH_2O gave 12.6 g of water on heating. Determine the value of x in the compound using mole concept.
Answer» <html><body><p></p>Solution :Weight of hydrated salt `Na_2SO_4.xH_2O = 26.8 g` <br/>Weight of water given by it = 12.6 g<br/> `therefore` Weight of anhydrous salt `Na_2SO_4 = 26.8 - 12.6 = 14.2g` <br/> Gram molecular mass of `Na_2SO_4 = (2 xx 22.99) + 32.06 + (4 xx 16.0) = 142.04 g`<br/> `therefore` Number of moles of `Na_2SO_4 = 142 04/(142.04) = 0.0999` <br/>and number of moles of `H_(2)O`associated with it `12.6/18.016`<br/> `therefore 0.0999` moles of `Na_2SO_4` <a href="https://interviewquestions.tuteehub.com/tag/attach-2449108" style="font-weight:bold;" target="_blank" title="Click to know more about ATTACH">ATTACH</a> moles of water = `0.699 , therefore` <a href="https://interviewquestions.tuteehub.com/tag/1-256655" style="font-weight:bold;" target="_blank" title="Click to know more about 1">1</a> <a href="https://interviewquestions.tuteehub.com/tag/mole-1100299" style="font-weight:bold;" target="_blank" title="Click to know more about MOLE">MOLE</a> of `Na_2SO_4` will attach moles of water <br/> `=0.699/0.0999 xx 1` <br/> = 6.99 <br/> =7, Hence, x=7</body></html>