BBC5 年
Reversible reactions, ammonia and the Haber process [Chemistry only]
Ammonia, NH 3, is an alkaline gas and so turns damp red litmus paper blue. Ammonium ions (NH 4 +) – found in ammonium compounds such as ammonium chloride, ammonium nitrate and ammonium sulfate ...
BBC11 年
What does the periodic table tell us about the elements?
Damp litmus paper is bleached white when it is placed in chlorine. If damp-blue litmus paper is used, the paper turns red then white.