Explanation:


Urea solution has molarity 4.0 mol/L and molality 2.273 mol/kg H20.


We need to find the density (g/ml) of the solution.


To find density, we need to use the formula:


Density = Mass/Volume


We know the molality of the solution, which is 2.273 mol/kg H20. This means that for every kilogram of water, there are 2.273 moles of urea present in the solution.


We can use this information to calculate the mass of urea present in the solution. We know that the molar mass of urea is 60.06 g/mol. Therefore, the mass of urea present in one kilogram of water is:


2.273 mol/kg H20 * 60.06 g/mol = 136.5 g/kg H20


Since the solution has a molarity of 4.0 mol/L, this means that there are 4.0 moles of urea present in one liter of the solution. We can use this information to calculate the mass of urea present in one liter of the solution:


4.0 mol/L * 60.06 g/mol = 240.24 g/L


Now we can use the density formula to calculate the density of the solution:


Density = Mass/Volume


The mass of one liter of the solution is the mass of urea plus the mass of water. Since the solution has a molality of 2.273 mol/kg H20, this means that there are 2.273 moles of urea present in one kilogram of water. Therefore, the mass of water in one liter of the solution is:


1 kg/L * 1000 g/kg - 136.5 g/L = 863.5 g/L


The total mass of one liter of the solution is:


240.24 g/L + 863.5 g/L = 1103.74 g/L


Therefore, the density of the solution is:


Density = 1103.74 g/L / 1 L = 1.10374 g/mL


Answer: 1.10374 g/mL.

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