What you're seeing when you put it through a prism is that you heat hydrogen up and it doesn't just glow like a white light, it just emits light at particular colors, a red one, a light blue one, some dark blue ones.
Cuando se ve esta luz a través de un prisma, la luz de hidrógeno incandescente, no brilla como una luz blanca, sino que emite luces de determinados colores, una luz roja, una azul, algunas azul oscuro.