Nitrogen And Sulfur Flashcards
Why is N2 unreactive
Has triple bond
High bond energy
Nitrogen reactions under extreme condition: acid rain formation
N2+O2>2NO
2NO+O2>2NO2
2NO2+H2O+.5O2>2HNO3
Haber process:
N2+3H2—>2NH3
Coordinate bond to make NH4+
Lone pair of N donated to H+ to form coordinate bond
Use of ammonium compounds/salts
Fertilisers
Eg nh4cl, nh4no3
Heat ammonium salt with alkali
Ammonia gas, goes thru calcium oxide for drying then turns litmus blue
Salt and water form too
How is nh4cl used to make fertiliser
Solution of it heated to evaporate the water and melt the solid. Solid solidified into pellets
Uses of nitric acid:
Make explosives
Detergents, paints and pigments and dyes
Environmental effect of nitrogen compounds
Fertilisers cause eutrophication.
Nitrates washed into lakes and are used by algae to grow. These block out light for plants. These die and bacteria use dissolved oxygen to decompose them. Oxygen rapidly used up and animals die. Ecosystem destroyed.
Problem with nitrogen oxides in the atmosphere
Acid rain and photochemical smog
NO2+SO2–>?
SO3+NO
SO3 can combine with h2o giving h2so4 ie acid rain
2 ways SO2 forms
Burn fossil fuels containing it
Released by Volcanoes
Bad effects of acid rain
Ph of water lowered. Plants and animals die
Nutrients washed away in soil
Buildings get corroded
How to reduce SO2 emission
Use little Sulfur having fuels
Remove Sulfur from fuel prior to burning
Remove so2 from waste gases before release into atmosphere
Contact process to make h2so4
S2+O2>SO2
2SO2+O2>2SO3 450°C, 2atm, vanadium V oxide catalyst
SO3+ conc H2SO4>H2S2O7
H2S2O7+H2O>2H2SO4
