sc8, acids and alkalis (paper 1) Flashcards
acids have a pH of
less than 7
alkalis have a pH of
more than 7
acids are a source of what ions
hydrogen, H+
alkalis are a source of what ions
hydroxide, OH-
true or false: strong acids dissociate completely in water producing higher concentrations of H+ ions, whereas weak acids have incomplete dissociation
true
true or false: strong acids dissociate incompletely in water producing lower concentrations of H+ ions, whereas weak acids have complete dissociation
false
why can a dilute solution of a strong acid have a similar pH and reactivity as a concentrated weak acid
because they have a similar concentration of hydrogen ions
define neutralisation
an acid that reacts with a base to form a neutral substance
define base
a substance that neutralises an acid
true or false: all alkalis are bases, but not all bases are alkalis
true
true or false: all bases are alkalis, but not all alkalis are bases
false
what does a base + acid produce
salt + water
what does a metal + acid produce
salt + hydrogen
what does a metal carbonate + acid produce
salt + water + carbon dioxide
how do you test for hydrogen
a lighted splinbt ignites hydrogen with a pop
