Question

amount of sample containing 80% Noah required to prepare 60 lt of 0.5 M solution

Answer 1

Hello Dear.
Volume of the solution = 60 liter.Molarity of the solution = 0.5 M.
Using the Formula,Molarity = No. of moles of solutes/Volume of the solutions in liter.∴ 0.5 = No. of moles/60⇒ No. of moles of NaOH = 30 moles.
Molar mass of the NaOH = 40 g/mole[∵ 23 + 16 + 1 = 40]
∵ No. of mole = Mass/Molar Mass∴ Mass = No. of moles × Molar Mass⇒ Mass = 30 × 40⇒ Mass = 1200 g.
∴ Mass of the NaOH = 1200 g.
Now, Let the Mass of the solution be x g.
According to the Question,
Mass of the NaOH = 80% of the Solution.1200 = (80/100) × x⇒ x = 15 × 100∴  x = 1500 g


Hence, the mass of the sample or solution is 1500 g.

Hope it helps.