Erasers help us get rid of our mistakes. The “lead” in the pencil is actually graphite, which is made up of carbon.
As you’re writing, the particles in the graphite in your pencil stick to the fibers on the paper. An eraser, on the other hand, is usually made of rubber but here and there, you’ll see ones made from plastic.
Erasers are mixed with sulfur to make them last longer, vegetable oil is added to soften them and make them more flexible. Abrasives and dyes also are added.
Erasers work because of friction, which is caused by two surfaces rubbing against one another. If you rub your hands, they becomes warmer. The same thing happens when you use an eraser. The heat from the friction causes the sticky part of the eraser to “grab” the graphite particles that have been loosened due to the abrasives in the eraser.
The paper doesn’t tear due to the softener in the eraser.
While the rubber is “grabbing” the graphite particles, there are pieces of the combined graphite and rubber left behind. Those are the annoying pieces of the eraser that you have to brush off your paper.
In 1770, Edward Naime, an English engineer, accidentally picked up a piece of rubber instead of the white bread that was used as an eraser at the time. When he used it, he noticed that the pencil marks were “rubbed off,” which is why it’s called “rubber” now!
