A satisfying blend of blue, white, and purple sand is sliced smoothly, revealing mesmerizing layers and textures beneath the ...

Indicators change color depending on whether they are mixed with an acid or a base ... only to find the stain an even darker purple-blue color! What does this tell you about the laundry detergent?

To start with I mix my primary colours to create secondary colours. Red and yellow make orange. Red and blue make purple. Yellow and blue make green. The third set of colours the tertiary colours ...