Chemical industry Flashcards
where does the low reactivity of nitrogen molecules arise from
strong triple bond
conditions for nitrogen gas to react
the triple bond must be broken
at high temperatures
in the presence of a catalyst
Describe the bonding in ammonia
Ammonia has three hydrogen bonds
And one lone pair this lone pair can form a dative covalent bond
How is Ammonium formed
Ammonia acts as a base when it forms a dative covalent bond with hydrogen ions
What is a dative covalent bond
When one atom donates both the shared paired of electrons
Where does Nitrogen oxide come from
And state its colour
Comes from combustion in vehicles
Thunderstorms
And denitrifying bacteria in soil
Appearance-colourless to brown in air
Where does Nitrogen dioxide come from
And state its colour
Nitrogen dioxide comes from the oxidation of nitrogen oxide
Appearance- its a brown gas
Where does dinitrogen oxide come from
And state its appearance
Dinitrogen oxide comes from denitrifying bacteria
Appearance- colourless gas
Describe how Nitrification takes place
Nitrification takes place by aerobic bacteria
Where the ammonium ions are oxidised into NO2- and then further oxidised into
NO3- ions
Nitrate ions are ———— in water
Soluble
How to test for nitrate ions?
Add devadras (Cu/Zn/Al) alloy and sodium hydroxide to a test solution and heat
Ammonia will evolve if nitrate ions are present
It will damp red litmus paper blue
How to test for ammonium ions?
Add sodium hydroxide to a test solution and gently heat.
Ammonia gas will be given off if ammonium ions are present.
What is Equilibrium concentration
The concentration reached when the reaction has reached equilibrium.
What does increasing the pressure do to the equilibrium and the equilibrium constant
It moves the equilibrium to the side with fewer moles
The equilibrium constant remains constant
What does changing the temperature do to the equilibrium and the equilibrium constant
It shifts the equilibrium to the endothermic side
The equilibrium constant is changed
