For ten points, name this chemical also used to ease cardiac pain.
First prepared by adding glycerol to a mixture of sulfuric and nitric acids, it's a liquid at room temperature but freezes easily. It is even more unstable in solid form, but, when mixed with a porous inert substance such as charcoal or kieselguhr its stability greatly increases, a property discoverd by Alfred Nobel. For ten points, name this chemical also used to ease cardiac pain.
First prepared by adding glycerol to a mixture of sulfuric and nitric acids, it's a liquid at room temperature but freezes easily.
nitroglycerin or glyceryl trinitrate (do not accept dynamite)