I have degrees in Chemical Engineering and have specialized in Computational Fluid Dynamics which is a Mechanical Engineering dominated field. When I attended BYU, Chemical Engineering was quite a bit more difficult than the other engineering majors with Electrical Engineering (my wife's major) the next hardest. The tough part of Chemical Engineering is that you have to take all the chemistry classes that a chemistry major needs but also the tough engineering classes (materials, thermodynamics, heat transfer, fluids) of a Mechanical Engineer and some uniquely difficult Chemical Engineering only subjects (like separations).

Things may change over time but Chemical Engineers have a very broad application space (microchip manufacturing to food science) that makes their breath of expertise wide.