Unit 4 - Explaining Chemical Changes 1 Flashcards
a substance that has a pH lower than 7
acid
a substance which reacts with materials and makes them dissolve
corrosive
something that reddens the skin
irritant
the atom present in all acids
hydrogen
a soluble base that has a pH higher than 7
alkali
the effect produced when an alkali is added to water
soapy
the particle present in alkalis
hydroxide
a dye that can change colour when placed in environments with different pH values
indicator
an indicator which tells us if something is an acid or an alkali
litmus
when a substance is neither acidic nor alkaline
neutral
contains a lot of hydrogen ions / particles (acid) or a lot of hydroxide ions / particles (alkali)
strong acid/alkali
contains only a few hydrogen particles / ions (acid) or a lot of hydroxide particles / ions (alkali)
weak acid / alkali
a mixture of dyes which create a range of colour depending on the strength of acidity or alkalinity being tested
universal indicator
the scale from 1-14 which shows acidity or alkalinity
pH number
when an acid and alkali combine resulting in products with pH 7
neutralisation
