wine left standing open turns sour
substances that change colour
when they are added to acidic
or alkaline solutions
commonly used indicators:
litmus, phenolphthalein, methyl orange
litmus indicator solution turns red in
acidic solutions, blue in alkaline
solutions, purple in neutral solutions
changes colour to
litmus paper comes as red paper
or blue paper, see table below
Red litmus
Blue litmus
Acidic solution
stays red
turns red
Neutral solution
stays red
stays blue
Alkaline solution
turns blue
stays blue
Acids turn blue
litmus paper red
Alkalis turn red
litmus paper blue
Acids & Bases - Terms & Definitions
Term
Definition
acids
substances with a sour taste that feel rough on the skin
bases
substances with a bitter tasted that feel slippery
properties
behaviour and characteristics
corrosive
describing a substance that eats through clothing,
stonework, metals and burns the skin
alkali
base that can dissolve in water
neutral
substance that is not an acid or a base
indicators
dyes that change colour in acids and bases
Complete the venn diagram below:
sour taste
feels slippery
corrosive
cleaning products
blue litmus paper turns red
fruits & juices
pH greater than 7
red litmus paper turns blue
pH less than 7
bitter
Acids & Bases - Terms & Definitions
Term
Definition
acids
bases
properties
corrosive
alkali
neutral
indicators
Venn diagram memo: