# Is BaSO4 (barium sulphate) soluble or insoluble in diluted HNO3 (nitric acid) and diluted HCl (hydrochloric acid)? [closed]

Here's the original question , I was asked in an exam :

Edit : the question in the picture is a single correct multiple choice question

I have concluded the the reaction of Barium chloride and Sodium sulphate will give BaSO4 as a white precipitate but I am having difficulty determining its solubility in HCl and HNO3

• Have you tried searching with keywords baryum sulphate solubility dilute mineral acids ? Oct 11 at 14:47
• Yes I did see you answer to that question and your conclusion that " The BaSO4 solubility in concentrated HCl is limited, in diluted one is very low The solubility in concentrated sulphuric acid would be much higher " , but in this scenario with HNO3 and HCl in frame , what could be the best answer to the question ( in the picture ) Oct 11 at 15:08
• My answers are not all available resources... :-) // The question is a wrong question, having 2 correct answers. Oct 11 at 15:13
• I did research a lot before asking this question here , tried to find YouTube videos of the reactions and articles but I was unable to find any such video on this reaction although there were some Quora threads which had contrasting answers Oct 11 at 15:17
• Rather ask yourself, why should be $\ce{BaSO4}$ soluble in dilute acids, if it is insoluble in water ? ( Be aware of rather fuzzy definition of insoluble.) Oct 11 at 15:19

$$\ce{BaSO4}$$ is insoluble in dilute solutions of acids, because this dissolution would produce the following ions in solution : $$\ce{Ba^{2+}, H^+}$$ and $$\ce{SO4^{2-}}$$. And the preceding reaction has shown that $$\ce{Ba^{2+}}$$ and $$\ce{SO4^{2-}}$$ cannot exist simultaneously in solution : they must react to produce a precipitate of $$\ce{BaSO4}$$.
On the other hand, Baryum sulfate is known to be soluble in hot and concentrated sulfuric acid, because of the formation of $$\ce{HSO4−}$$ ions. But $$\ce{BaSO4}$$ is not even soluble in hot concentrated hydrochloric acid, according to F.-P. Treadwell, Analytical Chemistry, 1924.
As a consqquence, the answers $$a)$$ and $$d)$$ are to be chosen without any doubt.
• @Oscar Lanzi. You are right. But the problem mentions "dilute solutions" . Baryum sulfate is known to be soluble in hot and concentrated sulfuric acid, because of the formation of $\ce{HSO4^-}$ ions. But $\ce{BaSO4}$ is not even soluble in hot concentrated hydrochloric acid, according to F.-P. Treadwell, Analytical Chemistry, 1924. Oct 11 at 15:35