brønsted -lowry model
DESCRIPTION
Brønsted -Lowry Model. Acids - proton (H + ) donors Bases – accepts proton (H + ). Brønsted -Lowry Model. A Br ø nsted -Lowry acid is a proton donor A Br ø nsted -Lowry base is a proton acceptor. Proton = Hydrogen ion = H +. - PowerPoint PPT PresentationTRANSCRIPT
Brønsted-Lowry Model
Acids - proton (H+) donorsBases – accepts proton (H+)
Brønsted-Lowry Model• A Brønsted-Lowry acid is a proton donor• A Brønsted-Lowry base is a proton acceptor
Proton = Hydrogen ion = H+
The Brønsted definition means NH3 is a BASE in water — and water is itself an ACID
BaseAcidAcidBaseNH4
+ + OH-NH3 + H2OBaseAcidAcidBase
NH4+ + OH-NH3 + H2O
H+
H+
H+
Can you see how the HCl gives up a proton (H+) to the H2O?
Acid donates the proton (H+), base accepts it.Which is the acid and which is the base in the forward reaction?
CH3CO2H + H2O H⇌ 3O+ + CH3CO2-
CH3CO2H (acetic acid) – proton donor
H2O (water = base) – proton acceptor
Brønsted-Lowry Model• Amphoteric – something that can act as an
acid or a base.
• Water is acting as both an acid and a base
Base Acid Acid Base
Conjugate Pairs
Base Pairs to AcidAcid Pairs to Base
Conjugate Pairs• NH3, NH4+
• H2O, OH-
What are the conjugate acid base pairs?HCl + H2O H⇌ 3O+ + Cl-
HCl (acid), Cl- (base)H2O (base), H3O+ (acid)
Conjugate Pairs
Learning Check!
Label the acid, base, conjugate acid, and conjugate base in each reaction:
HCl + OH- Cl- + H2O HCl + OH- Cl- + H2O
H2O + H2SO4 HSO4- + H3O
+ H2O + H2SO4 HSO4- + H3O
+