Question

In a titration a 15.00 cm3 sample of H2SO4 required 36.42 cm3 of 0.147 mol dm–3 NaOH solution for complete neutralization. What is the concentration of the H2SO4?

Answer 1

We have a titration here between an acid and a base.

Base: NaOH

Acid: H2SO4

When we get to the equivalence point, we can use this formula:

C x V )1 = C x V )2

1 is referred to the acid and 2 is referred to the base.

C is concentration in mol/dm^3 (remember dm^3 = L)

V is the volume in cm^3

For H2SO4)

C1 = unknown value

V1 = 15.00 cm^3

For NaOH)

C2 = 0.147 mol/dm^3

V2 = 36.42 cm^3

Now, from C1 x V1 = C2 x V2, we clear C1

C1 = C2 x V2 / V1 = 0.147 mol/dm^3 x 36.42 cm^3 / 15.00 cm^3 = 0.357 mol/dm^3

Answer: C1 = 0.357 mol/dm^3 , concentration of the acid