Acids Bases and Salts Flashcards
What are
alkalis?
soluble bases
What do you call substances which are both acids and bases?
amphoteric/amphiprotic
How do acids react in solution?
they release hydrogen ions
(H+)
How do alkalis act in solution?
they release hydroxide ions
(OH-)
What are acids and bases in terms of protons?
acids - proton ‘donors’
bases - proton ‘acceptors’
What is always formed when an acid and alkali react?
water
( H+ + OH- > H2O)
What are
strong acids?
acids which completely dissociate in water
so the acid is completely reacted by the end of the reaction
What are
weak acids?
acids which, when reacted, not all of the acid reacts and some of it remains as the original acid
What are some examples of
strong acids?
hydrochloric acid (HCl)
nitric acid (HNO3)
sulfuric acid (H2SO4)
What are some examples of
weak acids?
ethanoic acid (CH3COOH)
What are the two general examples of bases?
metal oxide, metal hydroxide
What products are formed when a metal and an acid are reacted?
salt + hydrogen
(MASH, metal + acid -> salt + hydrogen)
What products are formed when a base and an acid are reacted together?
water + salt
(BAWS, base + acid -> water + salt)
What products are formed when a metal carbonate and an acid are reacted?
water + carbon dioxide + salt
(CAWCS, metal carbonate + acid -> water + carbon dioxide + salt)
What type of salt does hydrochloric acid form?
metal chloride
What type of salt does sulfuric acid form?
metal sulfate
What type of salt does nitric acid form?
metal nitrate
What type of salt does ethanoic acid form?
metal ethanoate
Define
salt.
(chemistry definition)
the chemical compound that results when cations and anions form an ionic bond
What universal indicator colour would a pH range of < 2 produce?
red
What universal indicator colour would a pH range of 2 - 4 produce?
orange
What universal indicator colour would a pH range of 4 - 6 produce?
yellow
What universal indicator colour would a pH range of 7 produce?
green
What universal indicator colour would a pH range of 8 - 11 produce?
blue
What universal indicator colour would a pH range of > 12 produce?
purple
What is a more precise way of measuring pH than universal indicator?
a pH meter
What are the soluble salts?
- containing Sodium
- containing Nitrate
- containing Ammonium
- containing Potassium
- containing Ethanoate
- group I salts
- group VII salts (except silver and lead)
- containing sulfate (except lead and barium)
What are the insoluble salts?
- containing anions (except SNAPE)
- containing hydroxide (except SNAPE and barium)
How do you make
soluble salts?
- React the metal, metal oxide or metal carbonate with the acid until all of the acid has reacted (use an excess of metal and heat).
- Filter the mixture to remove the excess solid metal, metal oxide or metal carbonate that remains.
- Concentrate the filtrate by heating the solution.
- Allow the solution to cool and crystals to form.
How do you perform an
acid-alkali titration?
- Measure out the volume of the first solution and place into a conical flask.
- Add 2 drops of indicator to the conical flask.
- Measure the inital value on the burette and record in the results table.
- Add the second solution until the indicator changes colour. Add in drops toward the end point. Measure the volume on the burette and record in the results table.
- Once you have concordent results, repeat the experiment without indicator.
- Evaporate the water to leave your salt crystals.
Define
concordent results.
(for a titration)
two (or more) readings within 0.20cm3
What is the basic method of making
insoluble salts?
- Choose two solutions of soluble salts.
- React them together to form an insoluble salt.
- Filter the mixture to separate the insoluble salt.
- Rinse the solid with distilled water.
- Allow to dry.
