Detergents / cleaning materials
Cleaning means mostly: remove certain substances from where they should not be.
We clean dishes, we brush our teeths, we wash our hair, we clean the windows, etcetera.
How is that: removing dirt, unwanted substances?
Therefore we have lots of methods, but three are important categories:
- The physical way
Weap and sand, like brushing teeths. Tooth-paste contains an amount of Calcium carbonate, a solid tiny divided substance that helps you to remove tooth absorbed substances. Brushing means simple: the tiny particles sand the dirt away, like you clean a pan. Nowadays very tiny plastic grains are used that are polluting drinking and other water.
Trouble water can be filtrated; also very physical.
Another physical way is the use of certain solvents: aceton is an example. It is used as nail polish remover. Nail polish dissolves in aceton.
Such a process is sometimes consedered as a chemical process.
- The chemical way
Chemical reactions are applied to clean matter. The chemical reaction will be treated in the following modules, but here already an example:
Cooking pans regularly used to boil water (it happens also in washing machines and kettles) show after some time a thin layer of Calcium carbonate (Calcite).
It is not easy to remove physically; sanding will damage the pan of kettle or the heating element.
In this case you can use a (not too strong) acid, like vinegar, that reacts with Calcite.
the product is Calcium acetate that dissolves in water. So rinsing at the end takes the product and the dirty layer has gone.
Another example:
Chlorine can be used to clean water. The chlorine is an oxydator that reacts with some dirt that can be oxydated, like bacteria.
- The physical-chemical way
The use of solvents is in fact not completely chemical, nor completely physical, but kind of mix: physical-chemical.
The use of soap is a mix of chemical and physical cleaning. In a way, soap reacts with the dirt, but is also 'sands'.