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?
1)
H3PO4 molar mass = 98 g / mole
mass % = 85.5 %
density = 1.69 g / mL
formula : relation between mass % and molarity
molarity = mass % x 10 x density / molar mass
= 85.5 x 10 x 1.69 / 98
= 14.7 M
molarity = 14.7 M
2)
moles of urea = mass / molar mass
= 5.6 / 60
= 0.0933
moles of methanol = 30.1 / 32
= 0.961
mole fraction of urea = moles of urea / total moles
= 0.0933 / 0.0933 + 0.961
= 0.0902
mole fraction of urea = 0.0902
concentrated phosphoric acid solution is 85.5% H3PO4 by mass and has a density of 1.69 g/mL...
Calculate the mole fraction of phosphoric acid (H3PO4) in a 25.4% (by mass) aqueous solution. (Assume 750 mL of solution.) What is the molarity of the solution? What is the molality? (At 20 ° C, the density of phosphoric acid is 1.1462 g/mL and the density of water is 0.99823 g/mL.)
Chemistry (6 points) What is the mole fraction of urea, CO(NH2)2, in a solution prepared by dissolving 6.8 g of urea in 33.5 g of methanol, CH3OH?
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Concentrated hydrochloric acid is 38% HCl by weight and has a density of 1.19 g/mL. A solution is prepared by measuring 36 mL of the concentrated HCI, adding it to water, and diluting to 0.500 L. Calculate the approximate molarity of this solution from the volume, percent composition, and density. Answer:
Concentrated hydrochloric acid is 38% HCl by weight and has a density of 1.19 g/mL. A solution is prepared by measuring 67 mL of the concentrated HCl, adding it to water, and diluting to 0.800 L. Calculate the approximate molarity of this solution from the volume, percent composition, and density.
A solution is prepared by dissolving 20.2 mL of methanol (CH3OH) in 100.0 mL of water at 25 ∘C. The final volume of the solution is 118 mL. The densities of methanol and water at this temperature are 0.782 g/mL and 1.00 g/mL, respectively. For this solution, calculate mole percent M=4.18 m=4.93 percent by mass= 13.6% mole fraction= 8.15*10^-2
A solution is prepared by dissolving 20.2 mLmL of methanol (CH3OH)(CH3OH) in 100.0 mLmL of water at 25 ∘C∘C. The final volume of the solution is 118 mLmL. The densities of methanol and water at this temperature are 0.782 g/mLg/mL and 1.00 g/mLg/mL, respectively. For this solution, calculate each of the following. a. Molarity b. Molality C. Percent by mass d. Mole Fraction
What is the mole fraction of phosphoric acid in a solution that is 5% by mass phosphoric acid and has a density of 1.025 g/mL
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A solution is prepared by dissolving 27.75 g sulfuric acid, H2SO4, in enough water to make exactly 200.0 mL of solution. If the density of the solution is 1.1094 g/mL, what is 1. Weight % of H2SO4 in the solution? 2. Mole fraction of H2SO4 in the solution? 3. Molarity of H2SO4 in the solution? 4. Molality of H2SO4 in the solution?