This page lists the material from the old Edexcel syllabus which isn't covered by my new Edexcel IGCSE Chemistry book.
Some chemistry of ammonia and its compounds
The old syllabus says that you should be able to "describe the simple chemistry of aqueous ammonia, ammonium chloride, ammonium nitrate and ammonium sulphate". Edexcel clarified what they wanted in a separate document - the following is based on that, and you will see that there is very little that you won't already find in the book.
You have to know that ammonia is very soluble in water and forms an alkaline solution. The reaction is:
The ammonia dissolves in the water, and then reacts to a small extent to form ammonium and hydroxide ions. The presence of the hydroxide ions makes the solution alkaline.
You have to know that ammonia is a colourless, pungent gas, which is less dense than air. It is the only alkaline gas that you meet at GCSE, and is tested with damp red litmus paper which it turns blue. You will find that on page 93 of the book.
With regard to ammonium salts, you have to know that they are all soluble in water, and that they react with bases (such as sodium hydroxide) to produce ammonia. This last reaction is covered on page 95 of the book. The solubility pattern is in the table on page 82.
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