Acids, Bases and Salts Flashcards
(29 cards)
Ph scale
The pH scale is a measure of acidity or alkalinity of water soluble substances
Acids have what type of concentration
High concentration of hydrogen ions (H+) in aqueous
Bases have what type of concentration
High concentration of hydroxide ions (OH-) in aqueous
Ph indicators
Litmus paper and methyl orange
Litmus paper effects
Turns red in acid
Turns blue in alkali (soluble base)
No change in water
Methyl orange effects
Turns red in acid
Turns yellow in alkali (soluble base)
Orange in water (original colour)
Acid
A substance that generates hydrogen H+ ions in aqueous. It is a proton donor
Base
A substance that generates hydroxide ions (OH-) in aqueous. It is a proton acceptor.
Alkali
Soluble base
Neutralization
Neutralization is the process by which an acid and base react to form water
Insoluble bases
Metal oxides
Acid + Metal =
Salt + Hydrogen
Acid + base
Salt + water
Salt
Ionic compound
Acids + carbonates
Salt + Water + Carbon dioxide
Base + ammonium salts
Salt + water + ammonia
Strong Acid
A strong acid will have a high concentration of H+ ions because the molecules are completely ionized in aqueous solution e.g HCL
Strong base
A strong base will have a high concentration of OH- ions because the molecules are completely ionized in aqueous solution e.g NaOH
Weak acid
A weak acid will have a low concentration of H+ ions because the molecules are partially ionized in aqueous solution e.g ethanoic acid
(denoted by double arrow)
Weak base
A weak base will have a low concentration of OH- ions because the molecules are partially ionized in aqueous solution e.g ammonia
(denoted by double arrow)
Non-metal oxides are usually
neutral or acidic
What oxides do not react with acids or bases
Neutral oxides such as water, nitrogen (II) oxide, and carbon monoxide do not react with acids or bases
What oxides neutralize bases
Acidic oxides such as sulphur dioxide, sulphur trioxide, carbon dioxide, and oxides of phosphorus will turn litmus paper red and neutralize bases
Amphoteric Oxides
Amphoteric oxides react with either a base or acid to form salt and water. They have properties of both bases and acids.