We will make the indicator by soaking a paper in a solution of CoCl2.6H2O and allowed it to dry. The
theory is that on a humid day, with Le Chatelier’s Principle in effect, water from the humid air adsorbs
on the paper and pushes the equilibrium to the left changing the color from blue to pink. On the dry
day, there is less H2O and the equilibrium is pushed to the right making the paper blue. Temperature
has a small effect too.