1 / 11

General properties

General properties. ACIDS Taste sour Turn litmus React with active metals – Fe, Zn React with bases. BASES Taste bitter Turn litmus Feel soapy or slippery (react with fats to make soap) React with acids. blue to red. red to blue.

media
Download Presentation

General properties

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. General properties ACIDS • Taste sour • Turn litmus • React with active metals – Fe, Zn • React with bases BASES • Taste bitter • Turn litmus • Feel soapy or slippery (react with fats to make soap) • React with acids blue to red red to blue

  2. There are a number of definitions for acid and bases, depending on what is convenient to use in a particular situations Arrehenius • Acids – produce H+ • Bases - produce OH- • Acids – donate H+ • Bases – accept H+ • Acids – accept e- pair • Bases – donate e- pair only in water Bronsted-Lowry any solvent Lewis used in organic chemistry, wider range of substances

  3. Examples Arrhenius HCl NaOH Bronsted-Lowry HCl HCN NH3 :NH3 Lewis BF3 Neutralization In general: Acid + Base  Salt + Water All neutralization reactions are double displacement reactions. HCl + NaOH NaCl + HOH HCl + Mg(OH)2 H2SO4 + NaHCO3

  4. The Bronsted-Lowry Concept HCl + NH3 → NH4+ + Cl- Acid base conj. acid conj. base Conjugate pairs HClCl- Acis and conj. base CH3COOHCH3COO- Acis and conjugated base HNO3NO3- Acis and conjugated base NH4+NH3 Base and conj. acid How does a conjugate pair differ? H+transfer

  5. Let’s examine the behavior of an acid, HA, in aqueous solution. HA What happens to the HA molecules in solution?

  6. 100% dissociation of HA HA H+ Strong Acid A- Would the solution be conductive?

  7. Partial dissociation of HA HA H+ Weak Acid A- Would the solution be conductive?

  8. HA  H+ + A- HA H+ Weak Acid A- At any time, only a fraction of the molecules are dissociated.

  9. Strong and Weak Acids/Bases Strong acids/bases – 100% dissociation into ions HClNaOH HNO3KOH H2SO4 Weak acids/bases – partial dissociation, both ions and molecules are present CH3COOHNH3

  10. - H+ + H+ Amphoteric substances: substances that react with acids as a base and with bases as acids Acting like a base Acting like an acid HCO3- H2CO3 CO3-2 accepts H+ donates H+

  11. - H+ + H+ Show how water can be amphoteric. H2O H3O+ OH-

More Related