What color is black?
Some people answer with a simple “black,” while others respond with something like “black is the absence of all color.” If you have ever run out of black paint or your black pen ran dry, you probably know how to make the color black. Mix a little blue with red and yellow and green and orange and purple and you finally make the color black. Do the people who make black pens mix different colors to make black? Using a technique called chromatography, let’s find out exactly what makes up the color in that black pen.