Question

solution of 0.160 MNaOH is used to titrate 21.0 mL of a solution of H2SO4:H2SO4(aq)+2NaOH(aq)→2H2O(l)+Na2SO4(aq)If 38.8 mL of the NaOH solution is required to reach the endpoint, what is the molarity of the H2SO4 solution?

Answer 1

Answer:

0.0432 M H2SO4

Explanation:

First, we want to find the moles of MNaOH used. We know that Molarity x Liters = moles. 0.160M x 0.0210L = 0.00336 moles MNaOH

to find the moles of H2SO4, we can use a mol ratio.

0.00336mol MNaOH x (1Mol H2SO4 /2mol MNaOH)

= 0. 00168 mol H2SO4

I found the mol ratio by looking at the coefficients in front of the molecules I knew(MNaOH) and the molecule I needed to find(H2SO4)

then, to find Molarity, we do mol/Liters

0.00168 mol/ 0.0388L =. 0.0432 M H2SO4

You can convert mL to L by dividing by 1000

the significant figures of this problem is 3, so my final answer will also have 3 sig figs.