Analysing the Stars
It was possibly in a rash moment that the French philosopher Comte once remarked: "There are some things of which the human race must remain forever in ignorance; for example, the chemical composition of the heavenly bodies". Today it is possible to detect iron in the flames of the sun with just as much certainty as one can detect common salt in sea water. Analysis, one of a number of important phases of chemical investigation, involves finding the answer to two questions : What are the constituents present in the substance under investigation, and how much of each! For example, you might say to an analyst, here is a piece of beef steak ; does it contain sodium sulphite, and if so, how much! It is a relatively simple matter to carry out tests for the presence of sodium sulphite, i.e. to make a qualitative analysis.