Chemistry

A concentrated phosphoric acid solution is 85.5% H3PO4 by mass and has a density of 1.69 g/mL at 25°C. What is the molarity of H3PO4? What is the mole fraction of urea, CO(NH2)2, in a solution prepared by dissolving 5.6 g of urea in 30.1 g of methanol, CH3OH? How will an understanding of this concept help you in your healthcare career?