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

To find the molality of the solution, we need to calculate the moles of urea and the mass of the solvent (water) in kilograms.<br /><br />First, let's calculate the molar mass of urea (NH2CONH2):<br />- Nitrogen (N): 2 atoms × 14 g/mol = 28 g/mol<br />- Carbon (C): 1 atom × 12 g/mol = 12 g/mol<br />- Oxygen (O): 1 atom × 16 g/mol = 16 g/mol<br />- Hydrogen (H): 4 atoms × 1 g/mol = 4 g/mol<br /><br />Total molar mass of urea = 28 + 12 + 16 + 4 = 60 g/mol<br /><br />Next, let's calculate the moles of urea:<br />- Given mass of urea = 11 g<br />- Moles of urea = Given mass / Molar mass = 11 g / 60 g/mol = 0.1833 mol<br /><br />Now, let's calculate the mass of the solvent (water) in kilograms:<br />- Given mass of water = 200 g<br />- Mass of water in kilograms = 200 g / 1000 g/kg = 0.2 kg<br /><br />Finally, let's calculate the molality of the solution:<br />- Molality (m) = Moles of solute / Mass of solvent in kg = 0.1833 mol / 0.2 kg = 0.9165 mol/kg<br /><br />Therefore, the molality of the solution is 0.9165 mol/kg.