Question

A student with an unknown code of Q3A conducts a qualitative analysis of her unknown. Her results indicated the formation of a yellow precipitate and a grey precipitate. From her results, what ions can you confirm were not in her unknown sample?

Answer 1

Answer:

Grey precipitate implies the presence of silver ions

Yellow precipitate implies the presence of lead II ions

Explanation:

Qualitative analysis provides us a quick method of identifying ions present in a sample by chemical reactions involving simple reagents. Precipitates having a unique colour is formed. The identity of ions in the sample is deduced from the colour of precipitate obtained when particular reagents are added.

In the question, a precipitate containing silver ions upon standing turn into grey colour. Similarly, lead II ions give a yellow precipitate.