If you rub flea dirt on white paper, it will have a reddish-brown color. Why is this?

Interaction with Paper Fibers

When flea dirt, which is composed of flea droppings that contain dried blood, is rubbed on white paper, the color change to reddish-brown occurs due to the interaction between the dirt and the paper fibers.

When the dirt is rubbed on the paper, the dried blood particles in the dirt come into contact with the fibers of the paper. This interaction causes the color of the dirt to transfer onto the paper, resulting in a reddish-brown color.

It is important to note that if the dirt did not contain blood, or if the paper did not have fibers to interact with the dirt, the color change would not occur. Option C.

← Students lab experiment investigating aqueous solutions What is galena →