8 - Acids, bases and salts Flashcards
What is the effect of an acid on litmus paper?
Turns blue litmus paper red.
What is the effect of a base on litmus paper?
Turns red litmus paper blue.
What is the equation involving acid and base?
Acid + base → salt + water
What is the equation involving acid and metal carbonate?
Acid + metal carbonate → metal salt + carbon dioxide + water
What is an acid.
A proton donor with a pH less than 7.
What is a base.
A proton reciever with a pH more than 7.
What is a weak acid/base?
An acid/base that dissociates partially into a solution, leading to a low concentration of hydrogen/hydroxide ions.
What is a strong acid/base?
An acid/base that dissociates fully into a solution, leading to a high concentration of hydrogen/hydroxide ions.
Give an example of a neutral oxide.
Carbon monoxide
Give examples of amphoteric oxides.
Aluminium oxide
Zinc oxide
What is an amphoteric oxide?
An oxide that can react with both acids and bases.
Preparation of a metal salt.
Add excess metal to an acid
When release of hydrogen gas stops reaction is complete
Filter out excess metal
Preparation of an insoluble base.
Add insoluble base to acid and heat gently
Keep adding until no more dissolves
Filter out the excess insoluble base
Preparation of a soluble base (Titration)
1) Pour 25cm³ of the soluble base into a flask
2) Add phenolphthalein
3) Slowly add acid to the flask using a biurette and stir continuously
4) When the flask’s contents turn colorless record the volume of acid used
5) Repeat the steps without adding phenolphthalein
6) Pour the neutral solution into an evaporating dish and heat it
7) Evaporate the water out of the evaporating dish
What are the soluble salts?
Potassium, sodium and ammonium
Nitrates
Halides (Except silver and lead)
Sulphates (Except calcium, barium and lead)
