Question

Determine the number of moles of the anhydrous salt present after heating, assuming that the contents of the aluminum cup after heating are pure anhydrous KAl(SO 4 ) 2 .

Answer 1

Answer:

0.2 moles, assuming weight of dried salt

Explanation:

In order to determine the number of moles, we need to be aware of the mass of the substance in question.

Assuming the mass of the dehydrated $KAl(SO_{4} )_{2}.H_{2} O$ is 50g.

No. of moles = mass of substance/ molar mass of the substance.

= $\frac{50g}{39+27+32*2+16*4*2\\)g/mol}$

= 0.2 moles moles.