Baking soda
A can of baking soda
Baking soda, also called sodium bicarbonate (NaHCO3), is a dry, white powdery chemical compound that releases carbon dioxide when combined with certain acids.
In 2268, Leonard McCoy used a container of baking soda as a component of a gas grenade in an attempt to escape the Melkotian illusion. (TOS: "Spectre of the Gun")
In 2381, Lieutenant jg Beckett Mariner asked for baking soda, or something else with a pH above 7, after being exposed to the acidic blood of tremble lizards on Persioff IX. (LD: "The Inner Fight")
Baking soda was used by the visual effects department to create the sprays of snow as USS Voyager slammed into a Class L
planet in VOY: "Timeless".