ACID AND BASES Flashcards
what is an acid
a proton donor defined as a substance that can donate a proton
what is a base
a proton acceptor defined as a substance that can accept a proton
what is Ph
measure of acidity and alkalinity
why do we use a logarithmic scale
the concentration of hydrogen ions in aqueous solution covers a very wide range
how are ion concentrations determined
0 is classified as an acidic solution with high concentration of protons whereas 14 is a basic solution with a low concentration hydrogen ions
why is the concentration of hydrogen ions in a monoprotic strong acid the same concentration of the acid
because it completely dissociates to ions in a solution
what affects kw
the temperature if different to 25
what happens when temperature increases kw
the forward reaction is endothermic so it is more favoured when the temperature of water increases this means hydrogen ions are produced more and water is more acidic as temperature increases
what does a titration ph curve show
how the ph of a solution changes during an acid base reaction when they react a neutralisation point os reached which is identified as a large vertical section through neutralisation point
why do we use specific indicators
they can only indicate a ph change within a certain range
what is methyl orange used for
used for reaction with a more acidic neutralisation point- orange in acids turn yellow at the neutralisation point
what is phenolphthalein used for
used for reactions with a more basic neutralisation point- pink in alkalis and turn colourless at the neutralisation point
what is a buffer solution
maintains an approximate constant ph dispute dilution or addition of small amounts of acid or base
what is an acidic buffer solution
contains weak acid and the salt of the weak acid and basic buffer solution conatin. weak base and the salt of that weak base
define the role of buffer solution
a solution which is able to resists the change in ph when small volumes of acid or bases are added
does ph of buffer solution change
not much but the order of 0.1 and 0.01 units of PH when a small volume of acid or base is added
what happens when we add a small amount of acid
increases the concentration of acid in the buffer solution meaning overall the solution will be slightly more acidic
what happens when a small amount of base is added
decrease the concentration if base in the buffer solution meaning the overall solution will be slightly more basic
what is buffer solution used for industrially
buffer solutions are commonly used in nature to keep the system regulated, this is important because enzymes or reactions occurring in living organism often require a specific PH which can be maintained using a buffer solution
