Which fatty acid salt is soluble in water solutions? a) rcoo-k+ b) (rcoo-)2mg2+ c) (rcoo-)2ca2+ d) none are soluble

Answer is (A)
Pottasium and Sodium salts are soluble in water. When these soaps are added to hard water. Hard water contains calcium or magnesium ions and they form Magnesium or Calcuim salts. These salts of magnesium and calcium precipitates out and are insoluble in water. This precipitation is called as dirt (the exact word for dirt is not acceptable here). This process is considered as the disadvantage of soap as well as using hard water.

Hno3(aq) → h+(aq) + no3−(aq). picture ii best represents the strong acid hno3. strong acids are strong electrolytes