Acids and Bases Flashcards
What is a Bronsted-Lowry acid?
Acids are proton donors (donate H+ ions)
What is a Bronsted-Lowry base?
Bases are proton acceptors (accepts H+ ions)
What is an alkali?
A soluble base that produces OH- ions when added to water.
Common strong acids names and formulas (give three)
Hydrochloric acid - HCl, Sulfuric acid - H2SO4, Nitric acid - HNO3
Common strong base names and formulas (give two)
Sodium hydroxide - NaOH (or any other metal hydroxide), Oxide ion - (O)2-
Common weak acids names and formulas (give two)
Ethanoic acid - CH3COOH, Ammonium - (NH4)+
Common weak bases names and formulas (give two)
Ammonia - NH3, Sodium carbonate - Na2CO3 (any metal carbonate or hydrogencarbonate)
How to identify a Conjugate acid
A conjugate acid is the same as the starting base plus H+.
How to identify a Conjugate base
A conjugate base is the same as the starting acid minus H+.
Products of reaction between acid and metal
salt and hydrogen
Products of acid and metal carbonate or metal hydrogencarbonate
salt, carbon dioxide and water
Products of acid and metal hydroxide or metal oxide
salt and water
Strong acid definition and common examples
Strong acids ionise completely when dissolved in water. Examples include HCl, HBr, HI, HNO3 and H2SO4
weak acids definition and common examples
Weak acids ionise incompletely when dissolved in water. Examples include carboxylic acids (eg HCOOH and CH3COOH),
HF, HCN, HNO2, H2SO3
Calculation to find pH from H+ concentration
pH = – log [H+]
Calculation to find [H+] from pH
[H+] = 10^-pH
pH scale range for acids and bases
Each one-unit change in the pH scale corresponds to a ten-fold change in H+ concentration.
<7 acidic, 7 neutral, >7 basic/alkaline
Definition of a neutralisation reaction
An reaction between an acid and a base (ie a proton transfer) that produces an ionic salt and water as products.
Polyprotic Acids
Species that donates multiple protons, H+, during ionisation
Amphiprotic Species
Amphiprotic species can either donate or accept a proton, H+.
Monoprotic (include an example)
Species that donates one proton, H+, during ionisation
Example: HCl, HNO3 or NH4+
Diprotic (include an example)
Species that donates two protons, H+, during ionisation
Example: H2SO4 or H2CO3
Triprotic (include an example)
Species that donates three protons, H+, during ionisation
Example: H3PO4
Acidic Oxides
Acidic oxides reacting with water producing acids.
When an acidic oxide is dissolved in water, it will decrease the pH of the water sample due to the formation of H+ions. Some common examples for acidic oxides are CO2, NO2 and SO2.