1 / 13

ACIDS AND BASES

ACIDS AND BASES. Ionization of Water. Describe the relationship between the hydronium and hydroxide ion concentrations in water Include: the ion product of water, K w. Additional KEY Terms. Water is amphoteric. H +. HA + H 2 O ( l ) H 3 O + ( aq ) + A¯ ( aq )

lois
Télécharger la présentation

ACIDS AND BASES

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. ACIDS AND BASES Ionization of Water

  2. Describe the relationship between the hydronium and hydroxideionconcentrations in water • Include: the ion productof water, Kw Additional KEY Terms

  3. Water is amphoteric H+ HA + H2O(l) H3O+(aq) + A¯(aq) or B + H2O(l) BH+(aq) + OH¯(aq) H+

  4. Water particles collide - ions form • Water also dissociates into ions - self-ionization H2O(l) + H2O(l)H3O+(aq) + OH¯(aq) H2O(l) H+(aq) + OH¯(aq)

  5. Water reaches equilibrium with its ions ion product for water, Kw H2O(l) H+(aq) + OH¯(aq) KW = [H+][OH¯] KW = [H3O+][OH¯]

  6. At room temperature: Kw = [H+][OH-] = 1.00 x 10-14 Water is neutral - these ions must be a 1:1 ratio [H+] = [OH-] = 1.00 x 10-7 M Like all constants, the value of Kw varies with temperature.

  7. Like any reversible reaction, Le Chatelier's applies: OH- H+ + H2O Add a SB – increase [OH-] decrease [H+] Add a SA – increase [H+] decrease [OH-] This means that H+and OH¯ are BOTH present in any solution - whether they are acidic or basic. Kw = [H+][OH-] = 1.00 x 10-14

  8. n V 2.5 mol = 0.50 mol/L 5.0 L If 2.5 moles of hydrochloric acid is dissolved in 5.0 L of water, what is the [hydroxide ions]? HCl (s) H+(aq) + Cl¯(aq) M = Since HCl is a strong acid (100% dissociation): [H+] = 0.50 M

  9. How does the addition of HCl affect WATER’s equilibrium? Kw = [H3O+] [OH-] Amount contributed by self-ionization of water H2O(l) H+(aq) + OH¯(aq) 1.0 x 10-14 = [OH-] [0.50 ] + 1.0 x 10-7] [OH-] = 2.0 x 10-14 M

  10. 0.40 g of NaOH is dissolved in water to make a solution with a volume of 1.0 L. What is the hydronium ion concentration in this solution? NaOH (s) Na+(aq) + OH¯(aq) NaOH = 40.0 g/mol 0.40 g 1 mol = 0.010 M 1 L 40.0 g Since NaOH is a strong base(100% dissociation): [OH-] = 0.010 M

  11. How does addition of NaOH affect WATER’s equilibrium? Kw = [H3O+] [OH-] 1.0 x 10-14 = [H3O+] [0.010 ] + 1.0 x 10-7] [H+] = 1.0 x 10-12 M

  12. H2O(l) H+(aq) + OH¯(aq) KW = [H+][OH¯] = 1.00 x 10-14 Add a SA – increase [H+] decrease [OH-] Add a SB – increase [OH-] decrease [H+]

  13. CAN YOU / HAVE YOU? • Describe the relationship between the hydronium and hydroxideionconcentrations in water • Include: the ion productof water, Kw Additional KEY Terms

More Related