acids and bases Flashcards
define an acid
Bronsted Lowry definition of an acid is a species that donates a proton, H+, during an acid-base reaction
common acids
hydrochloric acid HCl
sulfuric acid H2SO4
nitric acid HNO3
phosphoric acid H3PO4
ethanoic acid CH3COOH
carbonic acid H2CO3
ammonium NH4+
acids change indicators?
blue litmus -> red
phenolpthalein -> colourless
methyl orange -> red
general properties of acids
-tend to be corrosive
-taste sour
-react with bases
-have a pH less than 7
-solutions can conduct an electric current
define a base
Bronsted Lowry definition of a base is a species that accepts a proton, H+, during an acid-base reaction
an alkali is a soluble base that dissociates hydroxide ions
bases change indicators?
phenolpthalein -> pink
methyl orange -> yellow
red litmus -> blue
general properties of bases
-have a slippery feel
-taste bitter
-are caustic
-react with acids
-have a pH above 7 (alkalis only)
-solutions can conduct an electric current
define ionisation
the process by which a chemical species gains or loses an electric charge
define dissociation
the process by which a molecule separates into smaller particles
common bases
sodium hydroxide NaOH
ammonia NH3
magnesium hydroxide Mg(OH)2
potassium hydroxide KOH
oxide O2-
calcium hydroxide Ca(OH)2
conjugates
acid and conjugate base = pair
this is where the acid, has donated a proton and thus the conjugate base has hydrogen less eg. H2O -> OH-
base and conjugate acid = pair
this is where the base, has accepted a proton and thus the conjugate acid has more hydrogen eg. H2O -> H3O+
what are amphiprotic species?
amphiprotic species can either donate or accept a proton, H+
these substances have the availability to accept or donate a proton eg. water
ionic equations
these are simplified equations that do NOT include any spectator ions (aqueous ions which do not react and remain dissolved in solution throughout a reaction)
eg. 2K(s) + 2H+(aq) -> 2K+ (aq) +H2 (g)
strength of acids or bases?
related to how willingly it will donate or accept a proton
strong acid?
one that will undergo complete ionisation when added to water, almost all acid molecules in the solution will donate proton to form aqueous H+ ions
three common = sulfuric acid, hydrochloric acid, nitric acid