CI - Nitrogen chemistry Flashcards
How does nitrogen occur naturally?
As a diatomic molecule.
What is the electron confirguration of nitrogen?
1s2 2s2 2p3
Where is nitrogen found in the periodic table?
At the top of group 5.
What type of bond (number) do two nitrogen atoms form together?
Triple.
Is nitrogen reactive?
No it is very unreactive as it has a triple bond.
What do nitrogen and hydrogen form?
Ammonia and ammonia ions.
What makes ammonia very soluble in water?
It can form hydrogen bonds with other molecules.
What are the oxides that nitrogen forms?
NO, N2O and NO2.
What is NO and what are its properties?
Nitrogen monoxide, nitric oxide or nitrogen(II) oxide.
It is a colourless gas.
What is N2O and what are its properties?
Dinitrogen monoxide, nitrous oxide or nitrogen(I) oxide.
(Laughing gas). It has a sweet smell and is also colourless.
What is NO2 and what are its properties?
Nitrogen dioxide or nitrogen(IV) oxide.
It is a brown gas, has a sharp odour and is toxic.
What do ammonium compounds react with?
NaOH.
How can you test whether a mixture contains ammonium ions?
By adding some NaOH to the solution and gently heating the mixture. If ammonium ions are present, they will react with the hydroxide ions and ammonia gas will be evolved.
Ammonia gas is alkaline, so you can confirm its identity using a damp piece of red litmus paper. If there is ammonia present, the paper will turn blue.
What do nitrates react with and in what conditions?
Aluminium in the presence of an alkali.
How do you test whether a solution contains nitrate(V) ions?
Warm the solution with NaOH solutions and some aluminium foil or a piece of Devarda’s alloy - a solid that contains aluminium.
In the presence of an alkali, the aluminium reduces the nitrate ions to produce ammonia gas.
So if ammonia gas is given of then a piece of damp red litmus paper will turn blue indicating that the solution must contain nitrate ions.
