Acids & Bases Flashcards
Arrhenius definition of an acid
A substance that dissociates in water to produce H+ ions
Arrhenius definition: strong acid
A substance that almost completely dissociates in water to give hydrogen ions
Arrhenius definition: weak acid
A substance that only slightly dissociates in water to give hydrogen ions
Arrhenius definition: Base
A substance that dissociates in water to produce OH- ions
Arrhenius definition: Strong base
A substance that almost complexity dissociates in water to give hydroxide ions
Arrhenius definition: Weak base
A substance that inky slightly dissociates in water to give hydroxide ions
Brønsted-Lowry definition: An acid
A proton donor
Strong acid- good proton donor
Weak acid- poor proton donor
Brønsted-Lowry definition: Base
A proton acceptor
Strong base- good proton acceptor
Weak base- poor proton acceptor
What are the limitations of the Arrhenius theory?
- Limited to reactions in water (unlike Brønsted-Lowry)
- Limited to bases that produce hydroxide ions in water (not all bases)
- Doesn’t take the existence of hydronium ions into account (unlike BL)
Conjugate base
An acid changes into its conjugate base when it donates a proton
Conjugate acid
A base changes into its conjugate acid when it accepts a proton
Conjugate acid-base pair
Any pair consisting of an acid and a base that differ by one proton
A salt
The substance formed when the hydrogen ion from an acid is replaced by a metal or an ammonium ion
Neutralisation
The reaction between an acid and a base to form a salt and water
Acid+base—> salt+water
Name 3 examples of neutralisation
- MEDICINE, excess HCL produced by stomach—> ulcers, an antacid preparation is taken to neutralise the acid
- AGRICULTURE, if soil is too acidic, farmers spread lime (CaO) to neutralise
- ENVIRONMENTAL PROTECTION, areas that suffer from acid rain, limestone is added to lakes / in tall chimneys of coal burning power plants