Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: miss_maple on 10/12/2008 07:36:27

Title: Why does barium react with dilute hydrochloric acid but not sulphuric acid?
Post by: miss_maple on 10/12/2008 07:36:27

Topic : Acid & Bases

Qns : Why barium reacts with dilute hydrochloric acid but appears not to react with dilute sulphuric acid ?

Pls ans this quick. im having a test 2mr.

♥miss maple♥

Title: Re: Why does barium react with dilute hydrochloric acid but not sulphuric acid?
Post by: lightarrow on 10/12/2008 12:41:31

Quote from: miss_maple on 10/12/2008 07:36:27

Topic : Acid & Bases

Qns : Why barium reacts with dilute hydrochloric acid but appears not to react with dilute sulphuric acid ?

Pls ans this quick. im having a test 2mr.

♥miss maple♥

H₂SO₄ reacts with Ba forming BaSO₄ which is insoluble, so it forms a thin layer on the metal's surface, preventing a further action of the acid.

Title: Why does barium react with dilute hydrochloric acid but not sulphuric acid?
Post by: miss_maple on 11/12/2008 04:13:28

oh ok ! does this apply only to barium or does it apply to any other metals ?

Title: Why does barium react with dilute hydrochloric acid but not sulphuric acid?
Post by: lightarrow on 12/12/2008 19:43:11

Quote from: miss_maple on 11/12/2008 04:13:28

oh ok ! does this apply only to barium or does it apply to any other metals ?

Only to those metals which react with (dilute) H₂SO₄ forming an isoluble layer (sulphate, oxide, ecc). PbSO₄ is also insoluble (but less insoluble than BaSO₄). Note that, instead, concentrated H₂SO₄ does dissolve those sulphates because they react forming hydrogen sulphates, which are soluble:

BaSO₄ + H₂SO₄ <--> Ba(HSO₄)₂

Aluminum also is insoluble in that acid because it forms a tick layer of Al₂O₃. Tin also should be insoluble. Other metals as Cu, Ag, Au, Pt, ecc., are too noble to react with a generic non-oxidant acid. Yes, someone could say that hot, conc. H₂SO₄ is oxidant too...
The story would be very long...