Chemistry in everyday life

Chemistry is present in every aspect of life, and here you can see a few examples. There are articles about the chemistry of everyday life, and also a few about physics, as it's also present in our daily life.             

Why the sky is blue?
What is cholesterol?	Why smoking is harmful?
The secret of pressure cooker	Making invisible ink
Why coffee keeps you awake?	The chemistry of love
Vegetables and colors	How soap cleans?
Lactose intolerance	Crying while cutting onions?
Decaffeinated coffee	About commercial milk
Diesel fuels	The octanes of gasoline