Assume that you have an aqueous solution of an unknown salt. Treatment of the solution with dilute NaOH, Na2SO4, and KCl produces no precipitate. Which of the following cations might the solution contain? (a) Ag+ (b) Cs+ (c) Ba2+ (d) NH4 +

Video transcript

Hello everyone today. We have the following problem consider solution with an unknown salt. When they lose solutions of sodium sulfate, sodium chloride and sodium sulfide were added to the solution. They all form a precipitate, identify the county on that a solution contains. So the fact that they all want to precipitate means that they were considered insoluble. And so right off the bat we can get rid of answer choices. A and C. For C, potassium is a group one a ion and these are all soluble. No exceptions with group one A ions with ammonia young, all ammonium salts, so all ammonium salts are soluble. No exceptions. That leaves answer choices B. And D. So we'll work with B 1st. We have led and if we react that led with first our sodium sulfate we get two ions of sodium and lead sulfate which is known to be in soluble according to the salt ability rules. So next we have to react our lead with our sodium chloride. In doing so we get one sodium ion as well as lead chloride which is also considered insoluble. According to our liability rules. And lastly we react our lead with our sodium sulfide. And this gives us two sodium ions as well as lead sulfide. And this once again will be insoluble. And so we have three for three insoluble ions when we are working with lead and so therefore that is going to make our answer be overall I hope this helped. And until next time