Gin and tonic of water, sugar, lime and gin to the quinine in order to make the drink more palatable, thus gin and tonic was born. Soldiers in India were already given a gin ration, and the sweet concoction made sense. Since it is no longer used as an antimalarial, tonic water today contains much less quinine, is usually sweetened, and is consequently much less bitter. Gin and tonic is a popular cocktail during the summer. A 2004 study found that after 12 hours, "considerable quantities (500 to 1,000 ml) of tonic water may, for a short period of time, lead to quinine
Hard water the effects of hard water on the surfactants. For this reason, water softening is often unnecessary. Where softening is practised, it is often recommended to soften only the water sent to domestic hot water systems so as to prevent or delay inefficiencies and damage due to scale formation in water heaters. A common method for water softening involves the use of ion exchange resins, which replace ions like Ca by twice the number of monocations such as sodium or potassium ions. Washing soda (sodium carbonate - NaCO) is easily obtained and has long been used as a water softener for