Question

Citric acid H3C6H5O7, occurs in plants. Lemons contain 5% to 8% citric acid by mass. The acid is added to beverages and candy. An aqueous solution is 0.688m citric acid. The density is 1.049 g/ml. What is the molar concentration?

Answer 1

m = mols/kg solvent
1 kg solvent has a mass of 1,000 g and a volume of v = m/d = 1000/1.049 = 953.3 mL or 0.9533 liters. Then Molarity = mols/L. You have 0.688 mols and you have 0.9533 L so the molarity = ??
check my thinking.

Answer 2

.722 mols/L

Answer 3

don't forget when finding the mass for the volume equation you must add the mass of your solute, citric acid. once you find the total mass, then divide by the density to give you the total volume. Then moles of citric acid divided by your total volume gives you the molarity, aka molar concentration.