1 / 21

Determining Hydrogen Ion Concentration in Strong and Weak Acids

This lab experiment focuses on determining the hydrogen ion concentration ([H+]) of strong acid HCl and weak acid acetic acid (HC2H3O2). Students will dissociate HCl completely, demonstrating its characteristics as a strong acid, while acetic acid's partial dissociation will illustrate its classification as a weak acid. By using various concentrations of HCl and indicators, students will compare their unknown acid with acetic acid, leading to the calculation of the acid dissociation constant (Ka). Safety precautions with goggles, gloves, and aprons are necessary.

naiya
Télécharger la présentation

Determining Hydrogen Ion Concentration in Strong and Weak Acids

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Our Next Lab

  2. Our Next Lab Determining Hydrogen Ion Concentration of Strong and Weak Acids.

  3. Our Next Lab HCl → H+ + Cl-

  4. Our Next Lab HCl → H+ + Cl- This is a strong acid

  5. Our Next Lab HCl → H+ + Cl- This is a strong acid It dissociates completely.

  6. Our Next Lab HCl → H+ + Cl- If one mole of HCl is dissolved in one liter of solution, then [H+] = 1 M

  7. Our Next Lab HCl → H+ + Cl- If one mole of HCl is dissolved in one liter of solution, then [H+] = 1 x 100 M pH = 0

  8. Our Next Lab HC2H3O2 ↔ H+ + C2H3O2-

  9. Our Next Lab HC2H3O2 ↔ H+ + C2H3O2- This is a weak acid

  10. Our Next Lab HC2H3O2 ↔ H+ + C2H3O2- This is a weak acid It does not dissociate completely.

  11. Our Next Lab HC2H3O2 ↔ H+ + C2H3O2- [H+] + [C2H3O2-] Ka = -------------------------- [HC2H3O2]

  12. Our Next Lab Your challenge, in today’s lab, is to experimentally determine Ka for HC2H3O2.

  13. Safety: Goggles Gloves Aprons.

  14. Groups: Work in groups of three or four One person in each group is the “manager.” the manager’s job is to keep track of directions Read the directions carefully Questions? Go to your manager first.

  15. Grades: Separate grades for activity and for write-up.

  16. Step 1: Label 12 test tubes: Set 1:Set 2: 0.1 M HCl 0.1 M HCl 0.01 M HCl 0.01 M HCl 0.001 M HCl 0.001 M HCl 0.0001 M HCl 0.0001 M HCl unknown unknown acetic acid acetic acid.

  17. Step 2: Follow written directions to mix up solutions.

  18. Step 3: Add one drop of methyl orange indicator to each solution in set 1. Add 1 drop of orange IV indicator to each solution in set 2.

  19. Data: The four different concentrations of HCl are your standard. Compare your unknown acid and your acetic acid to your standard solutions. Record your observations.

  20. Conclusions: The color will tell you the [H+]. The [H+] will tell you the pH. It will also let you calculate Ka. Answer the “Conclusions and Questions” at the end of your packet.

  21. 12 test tubes: Set 1:Set 2: 0.1 M HCl 0.1 M HCl 0.01 M HCl 0.01 M HCl 0.001 M HCl 0.001 M HCl 0.0001 M HCl 0.0001 M HCl unknown unknown acetic acid acetic acid. .

More Related