Fertilisation and Choosing reaction pathway Flashcards
What is a fertiliser
fertilisers replace the mineral ions needed by plants and so they promote growth
What is a Nitrogen fertiliser
they are a source of soluble nitrogen compounds
What acid is used to make ammonium sulphate
sulfuric acid
What acid is used to make ammonium nitrate
nitric acid
What is the preparation of ammonium sulphate like in a lab
Small scale, uses ammonia solution and dilute sulfuric acid, stages include titration and crystallisation and they are made in batches
What is the preparation of ammonium sulphate like in an industrial process
Large scale, Uses raw materials, there are several stages and it is continues
What materials are used to make ammonium sulfate
Sulfur, Natural gas, air, water
What factors are taken into account when deciding the reaction pathway
Cost, Availability, R of R, and yield/AE
What is the birkeland-eyde process like
Nitrogen + water = nitrogen monoxide
Nitrogen monoxide + oxygen = nitrogen dioxide
Nitrogen dioxide + water = nitric acid
Yield = 4%
What is the Ostwald process like
Ammonia + oxygen >< Nitrogen monoxide + water
Nitrogen monoxide + oxygen >< nitrogen dioxide
Nitrogen dioxide + oxygen + water = nitric acid
Yield = 95%, Exothermic reactions
Why might an industrial reaction not be allowed to reach equilibrium
If it is not profitable to reach equilibrium, then there is no point
Why does the Haber process not use high pressure and low temp
High pressure is expensive
Low temp reduces R of R
What is the chemical formula for the Haber process
N2 + 3H2 -> 2NH3
Why do we use
450 C
200 atm
when performing the Haber process
Needs to be hot for r of r however not to hot that the yield is decreased, heat is expensive
needs to be high pressure as there are few moles of product then reactants, high r of r (Inc freq of collisions)
