Acid & Bases Flashcards
What are ssome common acids and their uses?
Acetic acid - flavouring; preservative
Citric acid: flavouring
Phosphoric acid: rest remover
Boric acid: ,o;d amtosptic/insecticide
Hydrochloric acid: Brick / ceramic tile cleaner
Sodium hydroxide: oven cleaner
Ammonia: Household cleaner
Sodium carbonate: Water softener, grease remover
sodium hydrogen carbonate: Fire extinguisher, backing powder
What does Arrhenius define an acid as?
H+ producer in aqueous solution
What does Arrhenius define a base as?
OH- produced in aqueous solution
What does Bronsted Lowry define an acid as?
Proton (H+) donor
What does Bronsted Lowry define a base as?
Proton (H+) acceptor
What is H+?
H+ is short for H3O+ in the reaction which is hydronium
What is a strong acid/base?
A strong acid or base has equilibrium to the right (I.e. it is fully ionised/dissociatied). (Complete dissociation)
What is a weak acid/base?
A weak acid or base has equilibrium to the left (partial ionisation/dissociation)
What is Ka and Kb?
The acid dissociation constant (Ka) is a quantitative measure of the strength of an acid in solution while the base dissociation constant (Kb) is a measure of basicity—the base’s general strength.
Uses the same formula as in Keq, and ignore liquid and solid states
What is a conjugate acid
A conjugate acid, within the Brønsted–Lowry acid–base theory, is a chemical compound formed when an acid gives a proton (H +) to a base—in other words, it is a base with a hydrogen ion added to it, as it loses a hydrogen ion in the reverse reaction.
I.e. NH4+ is the conjugate acid of NH3
What is a conjugate base
A conjugate base is basically an acid that lost its hydrogen ion. Its formula is the acid formula, minus the hydrogen ion.
I.e. NH3 is the conjugate base of NH4+
What is meant by the autoionisation of water?
It is the ability of water to react with itself and form a hydronium and hydroxide ion. The ability of water to react with itself is known as autoionisation.
What is the ionisation/equilibrium constant for autoionisation of water?
Kw = 10^-14 = [H3O+][OH-]
What is [H+] in a neutral solution?
[H+] = [OH-] = 1.0 x 10^-7
What is [H+] in a acidic solution?
[H+] > 1.0 x 10^-7
What is [H+] in a basic solution?
[H+] < 1.0 x 10^-7
What is the pH equation?
-log[H+]
What is the pOH equation?
-log[OH-]
What is the relationship between pH and pOH?
pH + pOH = 14
What pH is acidic?
pH < 7
What pH is neutral?
pH = 7
What pH is basic?
pH > 7
What is a strong acid or base?
these completely ionise in water
Equilibrium is completely to the right –> Ka or Kb = infinity
What are some examples of strong acids (6)
H2SO4 (Sulfuric acid)
HCl (Hydrochloric acid)
HBr(Hydrobromic acid)
HI ( Hydroiodic acid)
HNO3 (Nitric acid)
HClO4 (Perchloric acid)