Acids, Base and salts Flashcards
what is an acid
a proton donor
what is a base
a proton acceptor
acidic oxide
an oxide that reacts with a base to form a salt and water
basic oxide
an oxide that reacts with an acid to form a salt and water
bases
substances that can react with acids and neutralise them to make a salt and water are called bases. They are usually metal oxides or metal hydroxides. For example, copper oxide and sodium hydroxide are bases.
what does acid and metal form
salt and hydrogen
what does acid and oxides form
salt and water
what does acid and carbonate form
salt and water and CO2
what does acid and alkalis form
salt and water
why is it important for to control acidity in the environment
plants like to grow where the PH is 7 so making the soil acidic can prevent them from growing.
acid can leak into rivers and lakes from factories which can damage ecosystems
classify oxides as either acidic or basic, related to metallic and non-metallic character of the other element
in general, metals react with oxygen in order to form basic oxides
in general, non-metals react with oxygen in order to form acidic oxides
test for ammonium
add a little dilute hydroxide solution and heat gently
if ammonia gas is given off, ammonium ions were present in the solution.
(Ammonia gas turns red litmus blue and has a sharp smell)
test for copper (ii), iron (ii), iron (iii) and zinc
add a few drops of dilute sodium hydroxide solution.
pale blue precipitate indicates copper (ii)
green precipitates iron (ii)
red-brown precipitate indicates iron (iii)
add more sodium hydroxide and ammonium hydroxide
if the precipitate dissolves, zinc is present
test for carbonate ions
add a little dilute hydroxide acid
if mixture bubbles and gives off gas, that turns limewater milky, carbonate ions were present
test for chloride ions
add an equal volume of dilute nitric acid
add silver nitrate solution
white precipitate indicates chloride ions
test for nitrate
add a little sodium hydroxide solution.
add some aluminium foil. Heat gently
if ammonia gas is given off, the unknown substance contains nitrate ions
test for sulfate
add an equal volume of dilute HCL.
then add barium nitrate solution
barium nitrate is insoluble, so if sulfate ions are present a white precipitate will form
test for ammonia (gas)
ammonia gas has a strong sharp smell and turns red litmus blue
test for CO2
turns limewater milky
test for chlorine
turns indicator paper white
test for Hydrogen
collect the gas in a tube and hold a lighted splint to it.
the gas burns with a squeaky pop
test for oxygen.
collect the gas in a tube and hold a glowing splint to it.
the splint will relight.
how to make salt
metal oxide, metal, metal hydroxide. the second part comes from acid
