Chemistry Question

• schi_zo

  2 Nov 09, 18:18

  Barium metal strips were added to aq solution of sulphuric(VI) acid. Extremely vigourous effervescence observed but reaction stopped prematurely, amount of gas collected was less than expected.

  So why the reaction stops prematurely and what is the gas that is produced?

  Best if the equations are given.

• UltimaOnline

  2 Nov 09, 18:39

  A layer of insoluble BaSO4(s) coats the Ba metal strips, preventing complete reaction between the acid and the metal.
• schi_zo

  2 Nov 09, 18:42

  Oh ok thanks. Any idea what is the effervescence observed? H2 gas or SO2 gas?

   

• forum-er93

  2 Nov 09, 18:57

  metal + acid -> salt + hydrogen gas

• schi_zo

  2 Nov 09, 19:00

  But if you take in account the half eqns, Ba oxidises to Ba2+ ions. And sulphate ions reduced to SO2 gas. So theres where im confused.

• UltimaOnline

  2 Nov 09, 19:14

  No. Sulfate(VI) ions are not reduced. Protons from the acid are reduced to hydrogen gas.
• schi_zo

  2 Nov 09, 19:19

  ok thanks alot! :)