Soru
30) What is the % by mass of sodium chloride in an aqueous solution that is 239 M and has a density of 1.01g/mL A) 2.36 B) 13.8 C) 7.83 D) 140. E) 19.6 Answer: B
Çözüm
4.4
(260 Oylar)
İlkay
Usta · 5 yıl öğretmeni
Uzman doğrulaması
Cevap
To find the percentage by mass of sodium chloride in the aqueous solution, we need to follow these steps:1. Calculate the mass of sodium chloride in 1 liter of the solution.2. Calculate the total mass of 1 liter of the solution.3. Use the formula for percentage by mass: (mass of solute / total mass of solution) * 100.Given:- Molarity (M) = 239 M- Density = 1.01 g/mLFirst, let's calculate the mass of sodium chloride in 1 liter of the solution:Mass of sodium chloride = Molarity * Molar mass of sodium chlorideMolar mass of sodium chloride (NaCl) = 58.44 g/molMass of sodium chloride = 239 M * 58.44 g/mol = 13,976.16 gNext, let's calculate the total mass of 1 liter of the solution:Density = 1.01 g/mLTotal mass of 1 liter of solution = Density * VolumeTotal mass of 1 liter of solution = 1.01 g/mL * 1000 mL = 1010 gFinally, let's calculate the percentage by mass of sodium chloride:Percentage by mass = (Mass of sodium chloride / Total mass of solution) * 100Percentage by mass = (13,976.16 g / 1010 g) * 100 ≈ 13.8%Therefore, the correct answer is B) 13.8.