Question

calculate the mass of water necessary to make a 1.26 molal h2so4 solution from 24.4 g of h2so4

Answer 1

in water solution of H₂SO₄ water is solvent and H₂SO₄ is solute

mass of H₂SO₄ = 24.4 gram , molar mass of H₂SO₄ = 98.079 gram/mole

no of moles = mass in gram/molar mass , substitute values to find no of moles of H₂SO₄

no of moles of H₂SO₄ = 24.4/98.079 = 0.24878 moles

no of moles of solute = no of moles of H₂SO₄ = 0.24878 moles

given molality of solution = 1.26 molal

we know formula , killogram of solvent = no of moles of solute x molality , substitute values in formula

killogram of water = 0.24878 x 1.26 = 0.3134628 killogram

ans 0.3134628 killogram water is necessary to make 1.26 molal solution from 24.4 gram of H₂SO₄