In it, an apparently normal-looking petri dish is treated so as to reveal a message when wetted with water vapor. The contrast between hydrophobic and hydrophilic surfaces, which is not visible to ...

Place petri dish on stage of overhead projector. Pour water into dish to a depth of ¼” to 3/8” Scoop a small amount of Pb(NO3)2 into the water at one side of the dish. Scoop a small amount of KI into ...

A 100mm petri dish containing water is placed on an overhead projector. When solid Pb(NO 3) 2 is place on one side and solid KI on the other, PbI2 precipitates in the center.

The sweet dessert is a carrot pudding made with generous amounts of milk, sugar, cardamom and water. From Diwali ... she prepared the dessert in mini petri dishes as a palate cleanser.