Question: what does 12 oz of water weigh?
Answer: A U.S. fluid ounce of water will weigh approx. 29.57 g, while 1 ounce of water will weigh 28.35 g, and an Imperial fluid ounce will weigh approx 1 ounce. The avoirdupois ounce is equal to 28.35 grams and the troy and apothecaries' ounce to 31.103 grams.