In general,chemicls are divided into 4 groups.
1.Chemicals used in everyday life e.g. soap,toothpaste,hair gel.
2.Chemicals used for medical purposes e.g. medicine.
3.Chemicals used for farming e.g. pesticides, fertilizers.
4.Chemicals used in factories.
Chemicals are often intentionally used in cooking for these reasons:
1.To conserve food.
2.To improve production.
3.To improve flavor,smell and color of food.
4.To enrich the food,for example,putting citamin D in milk.
Chemicals used in the food industry.
Chemicals used to color food.
People found out how to make food look more delicious by adding colors from natural products,such as red from beetroot and yellow from carrots,etc.