Alcohol itself is ethanol, dissolved in water after an ethanol solution, if you want to dilute the alcohol, it is very simple, add water to the alcohol will be diluted, generally speaking, add water is added completely sterile distilled water, here there is a problem, why do you want to dilute the alcohol, to dilute it is how much concentration? This is a very important thing, is to dilute it, add water to the side, add how much to dilute how much. This actually has a problem, for example, the alcohol dilution, later used for disinfection, because most of the purpose of alcohol is to do disinfection, if the concentration of alcohol dilution is too low, there is no disinfection, so that the dilution of alcohol is to add distilled water. If it is diluted to less than 65%, alcohol will not disinfection, so that the dilution of alcohol must calculate the amount of water added to know how much the concentration of alcohol after dilution, if it is to ensure that it is used for disinfection, must let its concentration between 65%-75%, our national standard concentration of alcohol for disinfection is 75%, in some countries the lowest 65%, for example, in the United Kingdom, they generally use 65%. They are generally used 65%, in our country is used 75%.