Question

Calculate the molarity (M) if 3.35g of H3PO4 is dissolved in water to give a total volume of 200mL

Answer 1

0.171 M

Step-by-step explanation:

Step 1: Given data

• Mass of H₃PO₄ (solute): 3.35 g

• Volume of solution (V): 200 mL

Step 2: Calculate the moles of solute

The molar mass of H₃PO₄ is 97.99 g/mol.

3.35 g × 1 mol/97.99 g = 0.0342 mol

Step 3: Convert "V" to liters

We will use the conversion factor 1 L = 1000 mL.

200 mL × 1 L/1000 mL = 0.200 L

Step 4: Calculate the molarity of the solution

We will use the definition of molarity.

M = moles of solute / liters of solution

M = 0.0342 mol/0.200 L = 0.171 M