7.2 Brønsted–Lowry Theory of Acids & Bases

(Brønsted–Lowry) acids

proton donors

Strong acids: h__, s__, n__
Weak acids: e__, any o__ acid

hydrochloric, sulfuric, nitric, ethanoic, organic

Strong bases (hydroxides): s__, p__
Weak bases: N__, a__

sodium, potassium, NH3, amines

Strong acids/bases
> f__ d__ in soln (NOT abt conc of acid) ;; dissociates into lots of __/OH^-
> equil so far right that → is used
>> e.g. HCl(g) → H⁺(aq) + Cl^-(aq) OR HCl(g) + __(l) → __(aq) + Cl^-(aq)
> H__ has 2 H⁺ that can ionise (H₂SO₄ is s__, HSO₄ is w__)

fully dissociates, H+, H2O, H3O+, H2SO4, strong, weak

Weak acid/bases
> p__ d__ in soln ;; lower H⁺/OH^- conc
> e__ p__ a little left so ⇌ used

partially dissociates, equil pos

Detecting strength of acid: pH
> if HA → H⁺ + A^-, stronger acids d__ more (more __ made) so use d__ pH meter or u__ i__ paper

dissociate, H+, diff, universal indicator

Detecting strength of acid: electrical conductivity
> stronger acids = d__ more H⁺ = c__ b__ so use digital conductivity meter

dissociates, conducts better

Detecting strength of acid: reactive metals
> as acid + metal → salt + __(g), stronger acids = d__ more __ = more H₂ made, more b__

H2, dissociates, H+, bubbles

Reactions
> acid + metal → salt + __(g)
> acid + base → salt + __(l) [H⁺(aq) + OH^-(aq) → H₂O(l)]
> acid + carbonate → salt + __(g) + __(l)

H2, H2O, CO2, H2O

pH titration curves
__ acid added to __ base (both lines flat)

strong, strong

pH titration curves
__ acid added to __ base (flat in __ region)

strong, weak, acidic

pH titration curves
__ acid added to __ base (flat in __ region)

weak, strong, alkaline

pH titration curves
__ acid added to __ base (curved in __ regions)

weak, weak, both

Indicator	Colour in acid	Colour in base	pH
M__ o__	__	__	3.1-4.4

methyl orange, red, yellow

Indicator	Colour in acid	Colour in base	pH
P__	__	__	8.2-10.0

phenolphthalein, colourless, pink

Indicator	Colour in acid	Colour in base	pH
B__ b__	__	__	6.0-7.6

bromothymol blue, yellow, blue