1. DR Gas Reactions in aqueous solutions

2. H 2 S gas Any Acid + ionic sulfur compound  H 2 S(g) Example: 2HNO 3 (aq) + Na 2 S (aq)  H 2 S (g) + 2NaNO 3 (aq)

3. HCN gas produced Any acids added with alkali cyanide salts produce HCN gas Example: HF (aq) + NaCN (aq)  HCN (g)+ NaF (aq)

4. SO 2 (g) Any acid + any sulfite  H 2 SO 3  breaks down into H 2 O( l ) + SO 2 (g) Example: 2HF(aq) + Na 2 SO 3 (aq)  2NaF (aq)+ H 2 SO 3  2NaF(aq) + H 2 O( l ) + SO 2 (g)

5. CO 2 (g) Any acid+ any carbonate  H 2 CO 3  breaks down into H 2 O( l ) + CO 2 (g) Example: 2HCl(aq) + CaCO 3 (aq)  CaCl 2 (aq)+ H 2 CO 3  CaCl 2 (aq) + H 2 O( l ) + CO 2 (g)

6. NH 3 (g) Any ammonium salt + any base with OH  NH 4 OH  breaks down into H 2 O( l ) + NH 3 (g) Example: 2NH 4 Cl(aq) + Ca(OH) 2 (aq)  CaCl 2 (aq)+ 2NH 4 OH  CaCl 2 (aq) + 2H 2 O( l ) + 2NH 3 (g) Ammonia is the only practical liquid fuel that can be made from water, air, and renewable energy that is clean burning. –Holbrook, Brave New Climate, 2007