Does anyone know an example of a reaction which produces gas?
Hello, all metals with oxidation potential higher than that of hydrogen produces gas when treated with an acid. For example, zinc is a good metal to produce hydrogen gas:
If you need nitrogen gas, then try this:
[tex](NH_4)_2Cr_2O_7 + heat\rightarrow N_2+Cr_2O_3+~H_2O[/tex]
For oxygen, you'll use hydrogen peroxide with acids on metal ions or any reducible substance:
[tex](NH_4)_2Cr_2O_7~+~H_2O_2~+~HCl \rightarrow CrCl_3~+~O_2~+~NH_4Cl~+~H_2O[/tex]
Also, ammonium salts give ammonia with heating with an alkali:
[tex]NH_4Cl~+~NaOH \rightarrow NH_3[/tex]
As a last example, carbon dioxide can be produced from carbonates:
[tex]Na_2CO_3~+~HCl \rightarrow CO_2[/tex]
I hope these are helpful. There are plenty more examples, but these were what I remembered quickly and wrote. You'll have to balance (and write the other unimportant products) for some reactions.
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