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K4FECN6

1.Why is it necessary to remove CO when ammonia is obtained by HABER'S process?
2.What is the role of desorption in the proces of catalysis?
3.What modification can be done to HARDY-SCHULZE law?(NCERT Part1 Pg-145)

nandithac

the reactant molecules which gets adrorbed on the surface of the catalyst for the reaction products to be formed needs to be removed after formation of the products for further reaction to take place this is accomplished by desorption

kasirajan.1990

1. NH₃ is removed to avoid the reverse rxn in habers process.

2.desorption makes the surface available again formore rxnz to occur.

3. c this
http://www.goiit.com/posts/list/physical-chemistry-what-modifications-can-u-suggest-on-hardy-44221.htm

Aatish

hey Kasiranjan I agree wid you for the 2nd and 3rd ones........

BUT for the 1st one.......I have not seen any CO coming out in HABER's PROCESS.......

Aatish

That must be Ammonia.....which is taken out.......

kasirajan.1990

yup ts ammonia...i hv changed it.

punnima

i think its this:
The hydrogen 4 d NH3 synthesis was made by d water-gas process (a Carl Bosch invention) which involves blowing steam through a bed of red hot coke resulting in d separation of hydrogen from oxygen. The nitrogen was obtained by distillation of liquid air, then by cooling and compressing air.

These days, the hydrogen is produced by reforming light petroleum fractions or natural gas (methane, CH4) by adding steam:
CH4(g) + H2O(g) Ni catalyst CO(g) + 3H2(g)
---------->
700*C

Enough steam is used to react with about 45% of the methane (CH4), the rest of the methane is reacted with air:
2CH4(g) + O2(g) + 4N2(g)
(air) Ni catalyst
---------> 2CO(g) + 4H2(g) + 4N2(g)

All the carbon monoxide (CO) in the mixture is oxidised to CO2 using steam and an iron oxide catalyst:
CO(g) + H2O(g) iron oxide catalyst H2(g) + CO2(g)
------------------>

The carbon dioxide (CO2) is removed using a suitable base so that only the nitrogen gas (N2) and hydrogen gas (H2) remain and are used in the production of ammonia (NH3).

punnima

since it is Haber-Bosch process for producn of ammonia

so it must b removal of CO₂ nd not CO

paddy.dude

this is so becoz CO acts as a poison and reduces the activity of the catalyst........so it is removed

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