Soru
10) A solution is prepared by dissolving 25.0 g of NaCl in 500.0 g of water. What is the molality (m) of NaCl in the solution? The density of the solution is 1.0g/mL A) 0.000856 B) 0.0500 C) 50.0 D) 8.56 E) 0.856
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4.3
(342 Oylar)
Devrim
Elit · 8 yıl öğretmeni
Uzman doğrulaması
Cevap
To calculate the molality (m) of NaCl in the solution, we need to follow these steps:1. Calculate the number of moles of NaCl: - Molar mass of NaCl = 58.44 g/mol - Number of moles of NaCl = 25.0 g / 58.44 g/mol = 0.429 mol2. Calculate the mass of the solvent (water) in kilograms: - Mass of water = 500.0 g = 0.5 kg3. Calculate the molality (m) using the formula: - Molality (m) = Number of moles of solute / Mass of solvent (in kg) ality (m) = 0.429 mol / 0.5 kg = 0.858 mTherefore, the molality (m) of NaCl in the solution is 0.858 m.The correct answer is E) 0.856.