Question

Green checks and red X's are not displayed for this question. Apply what you learned from the solubility labs to the following problems. (Note: You always apply tests to a small sample of a substance, never to a whole container.) A student finds two unlabeled jars of white, solid substances. It is believed that one of the jars contains K2SO4 and the other BaSO4. What is a quick means of telling them apart?

a) Add LiNO3 solution to each, Ba(NO3)2 will precipitate from BaSO4.
b) There is no way to easily tell the difference.
c) Add NaCl solution to each, KCl will precipitate from K2SO4.
d) Add water to each solid, K2SO4 is insoluble and BaSO4 is soluble.
e) Add LiNO3 solution to each, KNO3 will precipitate from K2SO4.
f) Add water to each solid, K2SO4 is soluble and BaSO4 is insoluble.
g) Add NaCl solution to each, BaCl2 will precipitate from BaSO4.

Answer 1

The quickest means of telling apart K2SO4 and BaSO4 is to add LiNO3 solution to each. Ba(NO3)2 will precipitate from BaSO4, indicating its presence.

Step-by-step explanation:

The quickest means of telling apart K2SO4 and BaSO4 is to add LiNO3 solution to each. Ba(NO3)2 will precipitate from BaSO4, indicating its presence. This is because BaSO4 is insoluble in water while K2SO4 is soluble. The net ionic equation for this reaction is: Ba²+ (aq) + SO² (aq) → BaSO4(s).