Soru
Example 5 11a of urea (NH_(2)CONH_(2)) was dissolved in 200g of water. What is the molality of the solution? Given N=14,C=12,O=16,H=1
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Elit · 8 yıl öğretmeni
Uzman doğrulaması
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To find the molality of the solution, we need to calculate the moles of urea and the mass of the solvent (water) in kilograms.First, let's calculate the molar mass of urea (NH2CONH2):- Nitrogen (N): 2 atoms × 14 g/mol = 28 g/mol- Carbon (C): 1 atom × 12 g/mol = 12 g/mol- Oxygen (O): 1 atom × 16 g/mol = 16 g/mol- Hydrogen (H): 4 atoms × 1 g/mol = 4 g/molTotal molar mass of urea = 28 + 12 + 16 + 4 = 60 g/molNext, let's calculate the moles of urea:- Given mass of urea = 11 g- Moles of urea = Given mass / Molar mass = 11 g / 60 g/mol = 0.1833 molNow, let's calculate the mass of the solvent (water) in kilograms:- Given mass of water = 200 g- Mass of water in kilograms = 200 g / 1000 g/kg = 0.2 kgFinally, let's calculate the molality of the solution:- Molality (m) = Moles of solute / Mass of solvent in kg = 0.1833 mol / 0.2 kg = 0.9165 mol/kgTherefore, the molality of the solution is 0.9165 mol/kg.