If an aqueous solution of urea n2h4co is 26% by mass and has density of 1.07 g/ml, calculate the molality of urea in the soln

Explanation:

Hello,

Molality is defined as:

Thus, as the solution is % by mass, one assumes that the mass of urea is 26g and the mass of the solution 100g, in such a way, one computes the moles of urea by knowing its molecular mass:

Now, as solution has a mass of 100g, the solvent has a mass of 74g which corresponds to 0.074L since the density of water is 1g/mL; in such a way the molality is:

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