what is the molarity of an unknown acid if 40.5 ml. of the acid can be titrated to an end point by 20.5 mL. of 0.2250 M NaOH

Molarity of Acid x Volume of acid = Molarity of Base x Volume of base

3. What is the molarity of an unknown acid if 40.5 mL of the acid can be titrated to an endpoint by 25.0 mL of 0.2250 M NaOH? Show calculations and be careful with significant figures.

To determine the molarity of the unknown acid, you can use the equation:

M₁V₁ = M₂V₂

Where:
M₁ is the molarity of the acid (unknown)
V₁ is the volume of the acid (unknown)
M₂ is the molarity of NaOH (0.2250 M)
V₂ is the volume of NaOH used (20.5 mL)

First, let's convert the volumes to liters:
V₁ = 40.5 mL = 40.5 mL/1000 mL/L = 0.0405 L
V₂ = 20.5 mL = 20.5 mL/1000 mL/L = 0.0205 L

Now we can substitute the values into the equation:
M₁ * 0.0405 L = 0.2250 M * 0.0205 L

Solve for M₁:
M₁ = (0.2250 M * 0.0205 L) / 0.0405 L

Calculating this:
M₁ ≈ 0.1147 M

Therefore, the molarity of the unknown acid is approximately 0.1147 M.

To find the molarity of the unknown acid, you can use the equation M1V1 = M2V2, where M1 is the molarity of the acid, V1 is the volume of acid used, M2 is the molarity of NaOH, and V2 is the volume of NaOH used.

In this case, you know the molarity of NaOH (0.2250 M), and you know the volume of NaOH used (20.5 mL). The volume of the acid used is 40.5 mL.

Using the formula M1V1 = M2V2, you can plug in the known values:

M1 * 40.5 mL = 0.2250 M * 20.5 mL

To solve for M1, rearrange the equation:

M1 = (0.2250 M * 20.5 mL) / 40.5 mL

Now you can calculate the molarity of the unknown acid:

M1 = 0.1159 M

Therefore, the molarity of the unknown acid is 0.1159 M.