Consider two food dyes $$ one is red and one is blue.

a$)$ Which has a smaller HOMO$-$LUMO gap?

b$)$ Will this absorb at a higher or lower wavelength?

Green Blue Yellow primary primary complementary complementary complementary Purple primary Orange Red THE VISIBLE SPECTRUM Wavelength in Nanometers 450 500 400 (ultra) Violet Blue Cyan 550 Green 600 650 700 Yellow Orange Red 750 (Infra)