A 20.0 % by mass solution of phosphoric acid (H₃PO₄)in water has a density of 1.114 g/mL at 20°C.What is the molarity of this solution? A)0.0114 M B)0.0568 M C)0.114 M D)2.27 M E)11.4 M

Question

Quizplus · Accepted Answer

To find the molarity, we first need to calculate the moles of phosphoric acid present in 1 L of the solution.

Let's assume we have 100 g (which is 20% by mass) of the solution. This means that 20 g of the solution is phosphoric acid.

Molar mass of H3PO4 = 3(1.01) + 1(30.97) + 4(16.00) = 98.00 g/mol
Number of moles of H3PO4 = (20 g)/(98.00 g/mol) = 0.204 moles

Now, we need to find the volume of the 100 g solution. We know that the density is 1.114 g/mL, so the volume is:

Volume = (100 g)/(1.114 g/mL) = 89.6 mL = 0.0896 L

Finally, we can calculate the molarity:

Molarity = (0.204 mol)/(0.0896 L) = 2.27 M

Therefore, the answer is D) 2.27 M.

A 200 % by Mass Solution of Phosphoric Acid (H3PO4)in Water

A 200 % by Mass Solution of Phosphoric Acid (H₃PO₄)in Water