Calculate the mass of urea (NH_(2) CONH_(2)) required in making 2.5 kgof 0.25 molar aqueous solution.

Calculate the mass of urea (NH_(2) CONH_(2)) required in making 2.5 kg

1.	Calculate the mass of urea (NH_(2) CONH_(2)) required in making 2.5 kgof 0.25 molar aqueous solution.
Answer» SOLUTION :`0.25` molar aqueous solution MEANS that Moles of urea `= 0.25 ` mole MASS of solvent (WATER) `=1 kg = 1000 kg` Molar mass of urea `= 14 + 2 + 12 + 16 + 14 + 2 =60 g mol ^(-1)` `therefore 0.25` mole of urea `= 60xx0.25 ` mole = 15 g Total mass of the solution `= 1000 + 15 g = 1015 g = 1. 015g` Thus, `1.015` kg of solution CONTAIN urea = 15 h `therefore 2.5 kg ` of solution will require urea `= (15)/(1.015) xx 2.5 kg =37g`