# chemistry

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the concentration of urea (MW=60.0g/mol) in a soltuion prepared by dissolving 16g of urea in 39g of H2O is ____ molal

• chemistry -

mols urea = grams/molar mass
m = mols/kg solvent = mols/0.039 = ?

• chemistry -

moles of urea:16(g)/60(g/mol)=0.267(mol)
39(g)*1(kg)/1000(g)=0.039kg
m=0.267/0.039=6.846(mol/kg)

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