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Calculate weight of Solute grequired fou moking
9.5 kg aqueous solution is given conc. of Solution
is 0.25m
:​

Answer 1

0.25 molal aqueous solution of urea means that 0.25 mole of urea are present in 1 kg of water

Moles of urea = 0.25mole

Mass of solvent (water) = 1 kg = 1000 g

Molar mass of urea (NH

2

CONH

2

) = 60 g mol

1. 0.25moleofurea=0.25mol×60gmol1=15g

Totalmassofsolution=1000+15g=1015g=1.015kg

Thus; 1.015 kg of solution contain urea = 15g×2.5kg of solution will require urea

1.015kg

15g

×2.5kg = 37 g