CHMA11H3 Lecture Notes - Lecture 7: Lone Pair, Ion, Conjugate Acid
93 views2 pages
21 Jan 2019
School
Department
Course
CHMA11 Lecture 7: Acids and Bases
- Defining acids and bases
o There are 3 naming schemes used to classify substances as acids and bases
▪ 1: Arrhenius Theory
• Only relevant for water and salts
• Acid: a substance that produces hydrogen ions in an aqueous
solution
• Base: a substance that produces hydroxide ions in an aqueous
solution
• Acid/Base interaction
o Essentially claims that the hydrogen ions from the acid will
combine with the hydroxide ions from the base to form
water
o The cation from the base will combine with the anion from
the acid to make a salt
o Therefore claims that all acids and bases combine to form
water and a salt
• Issues
o This theory does not handle bases without hydroxide ions
well
o The theory also doesn’t work when the involved acids and
bases are unable to form water
▪ 2: Bronsted-Lowry Bases
• Base: proton acceptors
o This theory claims that any material containing atoms with
lone pairs can be a bronsted lowry base
▪ These lone pairs attract positive protons toward
them due to their negative charge
o Hydroxide is the strongest base allowed in water
▪ Any stronger base will react with water to make
more hydroxide
• Acids: proton donors
o Any material able to release protons as hydrogen ions
▪ protons are always solvated in water
• we tend to think of them as H30+
• very rare for hydrogen ions to travel alone
• will travel together as H30+ due to the
strong hydrogen bonds
• Acid/Base interaction