Question

A quantity of 5 g of a crystalline salt when rendered anhydrous lost 1.8 g of water. The formula mass of the anhydrous salt is 160. The number of molecules of water of crystallization in the salt is​

Answer 1

$Amount of anhydrous salt left =5−1.8</p><p></p><p>=3.2 gram</p><p></p><p>Moles of anhydrous salt =1603.2=0.02</p><p></p><p>Moles of water =181.8=0.1</p><p></p><p>The ratio of anhydrous salt : water</p><p></p><p>0.020.02:0.020.10=1:5</p><p></p><p>∴ The number of molecules of water in salt =5</p><p></p><p>$