how to test water with salt?

first,use distillation
second,use dry cobalt(2) chloride test paper test the fraction
the paper change from blue to pink
after distillation, it remains some powder
it contains some salt
final,test different salt use different method
like flame test test the positive ion
use some solution test negative ion

"dehydrated Cobalt Chloride(dehydrated is a must)" can be used to test water
it will change colour from blue to pink when this salt react with water

1.Put some water into the test tube.
2.Use the spatula to add salt into the test tube.
3.Shake it.