Examples and Definitions Flashcards
what are acids?
acids are substances having H+ ions that react with OH- to form water
what happens when acids dissolve in water?
they ionise to form two ions, one of which is the hydrogen ion, H+. The H+ ion is responsible for the properties of acids.
what are the strong acids?
- nitric acid
- hydrochloric acid
- sulphuric acid
what acid is vinegar?
ethanoic acid (acetic acid)
hydrochloric acid
(hydrogen chloride)
HCl
nitric acid
(hydrogen nitrate)
HNO3
sulphuric acid
(hydrogen sulphate)
H2SO4
what are bases?
bases are substances that react with H+ ions of acids to form water.
any compound that can neutralise an acid is called a base
ammonia solution
NH3
what are soluble bases called
alkalis
what are neutral substances
substances which do not affect the colour of litmus or other indicators
how can the pH of a solution be determined
by using universal indicators
what is a pH scale
a measure of acidity and alkalinity
what is the range of the pH scale?
1 to 14
pH less than 7
acidic
pH equal to 7
neutral
pH more than 7
alkali/basic
what is a commonality in alkalis
“hydroxide” (OH)
what is a pH indicator
a weak acid solution that changes colour in the presence of an acid or alkali
what colour is litmus in acid
red
what colour is litmus in alkali
blue
what colour is bromothymol blue in acid
yellow
what colour is bromothymol blue in alkali
blue
what colour is phenolphthalein in acid
colourless
what colour is phenolphthalein in alkali
pink
what colour is methyl orange in acid
red
what colour is methyl orange in alkali
yellow
