Scotch mixer is a term used to describe a type of alcoholic beverage made with scotch whisky and a mixer, such as SODA or club SODA. The two most common mixers for scotch are SODA (4 letters) and club SODA (8 letters). Club SODA is a carbonated water that has been infused with minerals, such as sodium bicarbonate, potassium sulfate, and potassium chloride. It is often used in mixed drinks because it does not contain any calories or sugar.