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Acids and Bases. Acids & Bases. Water and acid combine in an exothermic reaction - releasing large amounts of heat. Water and acid combine in an exothermic reaction - releasing large amounts of heat. Acid - Base Theories. Lavoisier Arrhenius Bronsted-Lowry Lewis.
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Acids and Bases
Water and acid combine in an exothermic reaction - releasing large amounts of heat.
Water and acid combine in an exothermic reaction - releasing large amounts of heat.
Acid - Base Theories • Lavoisier • Arrhenius • Bronsted-Lowry • Lewis
Lavoisier - 1777 Acidity is caused by the presence of oxygen in the compound.
Lavoisier - 1777 He even created the word oxygen - from the Greek oxys, "sour" and genes, "born"
Lavoisier - 1777 Oxygen means "acid maker".
Lavoisier - 1777 Lavoisier's idea about acids turned out to be wrong...
Lavoisier - 1777 but it is historically important since it is the first scientific attempt to chemically characterize acids and bases.
Each theory includes more substances as acids and bases Arrhenius Bronsted-Lowry Lewis
Arrhenius Acid Any substance that produces hydrogen ions, H+, in water solution.
Arrhenius Base Any substance that produces hydroxide ions, OH-, in water solution.
In a formula, such as HCl, the positive part of a Arrhenius acid will ALWAYS be hydrogen.
In a formula, such as NaOH, the negative part of a Arrhenius base will ALWAYS be hydroxide.
Arrhenius acids and bases, and soluble salts, are called electrolytes.
When each dissolves, ions are released that conduct electricity.
If a solution has NO ions, it cannot conduct electricity.
Bronsted-Lowry Theory JohannesNicolausBronsted
Bronsted-Lowry Theory ThomasMartinLowry
Bronsted-Lowry Acid Any substance that acts as a proton donor.
Bronsted-Lowry Acid A B-L acid MUST have hydrogen somewhere in its formula.
Bronsted-Lowry Acid When an electron is removed from a hydrogen atom... - +
Bronsted-Lowry Acid a hydrogen ion is produced - a proton. +
Bronsted-Lowry Base Any substance that acts as a proton acceptor.
Bronsted-Lowry Base Most negative ions can acts as B-L bases.
Bronsted-Lowry Theory The acid/base definitions are broadened because no specific ion must be formed, although hydrogen is the only source of protons.
Bronsted-Lowry Theory The hydronium ion is formed by combining a hydrogen ion and a water molecule. H2O + H+ H3O+
Bronsted-Lowry Theory conjugate base
Bronsted-Lowry Theory A conjugate base is the particle that remains AFTER an acid gives up a proton.
Bronsted-Lowry Theory conjugate acid
Bronsted-Lowry Theory A conjugate acid is the particle formed when a base accepts a proton.
HCl + H2O Cl- + H3O+ Identify the B-L acid in this equation. What gives up a proton from the left side to the right?
HCl + H2O Cl- + H3O+ HCl donates a proton, it is the B-L acid.
HCl + H2O Cl- + H3O+ Identify the B-L base in this equation. What gains a proton from the left side to the right?
HCl + H2O Cl- + H3O+ H2O accepts a proton, it is the B-L base.
HCl + H2O Cl- + H3O+ Identify the conjugate base in this equation. What is left when the acid gives up a proton?
HCl + H2O Cl- + H3O+ Cl- is left when HCl gives up a proton, it is the conjugate base.
HCl + H2O Cl- + H3O+ Identify the conjugate acid in this equation. What is formed when the base accepts a proton?
HCl + H2O Cl- + H3O+ H3O+ is formed when water accepts a proton, it is the conjugate acid.
HCl + H2O Cl- + H3O+ acids have conjugate bases
HCl + H2OCl- +H3O+ bases have conjugate acids
Remove a proton from an acid to get its conjugate base. H2SO4 HI H2O
Remove a proton from an acid to get its conjugate base. H2SO4 HI H2O HSO4-
Remove a proton from an acid to get its conjugate base. H2SO4 HI H2O HSO4- I-
Remove a proton from an acid to get its conjugate base. H2SO4 HI H2O HSO4- I- OH-