Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

4 Jump to... Calisse Eids Question 15 of 20 Sapling Learning You need to determi

ID: 551167 • Letter: 4

Question

4 Jump to... Calisse Eids Question 15 of 20 Sapling Learning You need to determine the concentration of a sulfuric acid solution by titration with a standard sodium hydroxide solution. You have a 0.1008 M standard solution. You take a 25.00 mL sample of the original acid solution and dilute it to 250.0 mL. You then take a 10.00 mL sample of the dilute acid solution and titrate it with the standard solution. You need 18.43 mL of the standard solution to reach the endpoint. What is the concentration of the original acid solution? Number Concentration =

Explanation / Answer

H2SO4 + 2 NaOH ------------> Na2SO4 + 2 H2O

Moles of NaOH = volume x concnetration of NaOH

                         = 18.43 x 0.1008 / 1000

                         = 1.8577 x 10^-3 mol

Moles of H2SO4 in 10 mL of diluted solution = 1/2 x moles of NaOH

                                                  = 1/2 x 1.8577 x 10^-3

                                                  = 9.2887 x 10^-4 mol

Moles of H2SO4 in 25 mL of original solution = moles of H2SO4 in 250 mL of diluted solution

                                                  = 250/10 x9.2887 x 10^-4

                                                 = 0.02322 mol

Concentration of original solution = moles/volume

                                                    = 0.02322 /0.025

Concentration of original solution = 0.929 M

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote