Mix all ingredients together. Carefully pour the mixture into 6 tall (6-ounce) plastic bags so each is three-quarters of the way full, then add a lime slice to each and seal. Place the bags on a tray and freeze until solid, about 1 hour. Thaw 10 to 20 minutes before serving. (Thaw less time and it will be a slush; thaw longer and it will be a drink.)