Qualitative Analysis
Simple yes or no
We carry out some chemical analyses ourselves using simple, inexpensive kits that we buy from a pharmacist. Pregnancy tests, for example, give a simple yes or no answer to the question “Am I pregnant?”
Diabetes sufferers use a self-diagnosis kit to detect glucose in urine. A test strip is dipped in the urine and left for ten seconds. The colour of the strip changes. By matching it with standard colours, you can tell if there’s glucose present.
These sorts of chemical test kits aren’t just for medical purposes, though. You can buy kits to test chlorine levels, hardness or acidity in water or to see how much nitrogen, phosphorous and potassium is present in soil samples.
They are often referred to as “semi-quantitative” (rather than qualitative) chemical tests. That’s because, as well as telling you if a substance is present, they give a rough indication of how much of the substance is present.
Home drug test kit
Home testing kits are now available to check if people have taken illegal drugs.
The urine testing device – which can detect traces of six different drugs including cannabis, cocaine and heroin – has been met with mixed views.
Some say it’s a good way to stop people taking drugs. The Home Office believes it could damage relationships between parents and their children.